Ischemic injury to the OPTIC NERVE which usually affects the OPTIC DISK (optic neuropathy, anterior ischemic) and less frequently the retrobulbar portion of the nerve (optic neuropathy, posterior ischemic). The injury results from occlusion of arterial blood supply which may result from TEMPORAL ARTERITIS; ATHEROSCLEROSIS; COLLAGEN DISEASES; EMBOLISM; DIABETES MELLITUS; and other conditions. The disease primarily occurs in the sixth decade or later and presents with the sudden onset of painless and usually severe monocular visual loss. Anterior ischemic optic neuropathy also features optic disk edema with microhemorrhages. The optic disk appears normal in posterior ischemic optic neuropathy. (Glaser, Neuro-Ophthalmology, 2nd ed, p135)
A maternally linked genetic disorder that presents in mid-life as acute or subacute central vision loss leading to central scotoma and blindness. The disease has been associated with missense mutations in the mtDNA, in genes for Complex I, III, and IV polypeptides, that can act autonomously or in association with each other to cause the disease. (from Online Mendelian Inheritance in Man, http://www.ncbi.nlm.nih.gov/Omim/, MIM#535000 (April 17, 2001))
The 2nd cranial nerve which conveys visual information from the RETINA to the brain. The nerve carries the axons of the RETINAL GANGLION CELLS which sort at the OPTIC CHIASM and continue via the OPTIC TRACTS to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the SUPERIOR COLLICULI and the SUPRACHIASMATIC NUCLEI. Though known as the second cranial nerve, it is considered part of the CENTRAL NERVOUS SYSTEM.
Conditions which produce injury or dysfunction of the second cranial or optic nerve, which is generally considered a component of the central nervous system. Damage to optic nerve fibers may occur at or near their origin in the retina, at the optic disk, or in the nerve, optic chiasm, optic tract, or lateral geniculate nuclei. Clinical manifestations may include decreased visual acuity and contrast sensitivity, impaired color vision, and an afferent pupillary defect.
Hereditary conditions that feature progressive visual loss in association with optic atrophy. Relatively common forms include autosomal dominant optic atrophy (OPTIC ATROPHY, AUTOSOMAL DOMINANT) and Leber hereditary optic atrophy (OPTIC ATROPHY, HEREDITARY, LEBER).
Peripheral, autonomic, and cranial nerve disorders that are associated with DIABETES MELLITUS. These conditions usually result from diabetic microvascular injury involving small blood vessels that supply nerves (VASA NERVORUM). Relatively common conditions which may be associated with diabetic neuropathy include third nerve palsy (see OCULOMOTOR NERVE DISEASES); MONONEUROPATHY; mononeuropathy multiplex; diabetic amyotrophy; a painful POLYNEUROPATHY; autonomic neuropathy; and thoracoabdominal neuropathy. (From Adams et al., Principles of Neurology, 6th ed, p1325)
The portion of the optic nerve seen in the fundus with the ophthalmoscope. It is formed by the meeting of all the retinal ganglion cell axons as they enter the optic nerve.
Atrophy of the optic disk which may be congenital or acquired. This condition indicates a deficiency in the number of nerve fibers which arise in the RETINA and converge to form the OPTIC DISK; OPTIC NERVE; OPTIC CHIASM; and optic tracts. GLAUCOMA; ISCHEMIA; inflammation, a chronic elevation of intracranial pressure, toxins, optic nerve compression, and inherited conditions (see OPTIC ATROPHIES, HEREDITARY) are relatively common causes of this condition.
Inflammation of the optic nerve. Commonly associated conditions include autoimmune disorders such as MULTIPLE SCLEROSIS, infections, and granulomatous diseases. Clinical features include retro-orbital pain that is aggravated by eye movement, loss of color vision, and contrast sensitivity that may progress to severe visual loss, an afferent pupillary defect (Marcus-Gunn pupil), and in some instances optic disc hyperemia and swelling. Inflammation may occur in the portion of the nerve within the globe (neuropapillitis or anterior optic neuritis) or the portion behind the globe (retrobulbar neuritis or posterior optic neuritis).
Injuries to the optic nerve induced by a trauma to the face or head. These may occur with closed or penetrating injuries. Relatively minor compression of the superior aspect of orbit may also result in trauma to the optic nerve. Clinical manifestations may include visual loss, PAPILLEDEMA, and an afferent pupillary defect.
Diseases of the peripheral nerves external to the brain and spinal cord, which includes diseases of the nerve roots, ganglia, plexi, autonomic nerves, sensory nerves, and motor nerves.
Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.
Neurons of the innermost layer of the retina, the internal plexiform layer. They are of variable sizes and shapes, and their axons project via the OPTIC NERVE to the brain. A small subset of these cells act as photoreceptors with projections to the SUPRACHIASMATIC NUCLEUS, the center for regulating CIRCADIAN RHYTHM.
A group of slowly progressive inherited disorders affecting motor and sensory peripheral nerves. Subtypes include HMSNs I-VII. HMSN I and II both refer to CHARCOT-MARIE-TOOTH DISEASE. HMSN III refers to hypertrophic neuropathy of infancy. HMSN IV refers to REFSUM DISEASE. HMSN V refers to a condition marked by a hereditary motor and sensory neuropathy associated with spastic paraplegia (see SPASTIC PARAPLEGIA, HEREDITARY). HMSN VI refers to HMSN associated with an inherited optic atrophy (OPTIC ATROPHIES, HEREDITARY), and HMSN VII refers to HMSN associated with retinitis pigmentosa. (From Adams et al., Principles of Neurology, 6th ed, p1343)
Dominant optic atrophy is a hereditary optic neuropathy causing decreased visual acuity, color vision deficits, a centrocecal scotoma, and optic nerve pallor (Hum. Genet. 1998; 102: 79-86). Mutations leading to this condition have been mapped to the OPA1 gene at chromosome 3q28-q29. OPA1 codes for a dynamin-related GTPase that localizes to mitochondria.
The X-shaped structure formed by the meeting of the two optic nerves. At the optic chiasm the fibers from the medial part of each retina cross to project to the other side of the brain while the lateral retinal fibers continue on the same side. As a result each half of the brain receives information about the contralateral visual field from both eyes.
The total area or space visible in a person's peripheral vision with the eye looking straightforward.
Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.
Swelling of the OPTIC DISK, usually in association with increased intracranial pressure, characterized by hyperemia, blurring of the disk margins, microhemorrhages, blind spot enlargement, and engorgement of retinal veins. Chronic papilledema may cause OPTIC ATROPHY and visual loss. (Miller et al., Clinical Neuro-Ophthalmology, 4th ed, p175)
A flavoprotein and iron sulfur-containing oxidoreductase that catalyzes the oxidation of NADH to NAD. In eukaryotes the enzyme can be found as a component of mitochondrial electron transport complex I. Under experimental conditions the enzyme can use CYTOCHROME C GROUP as the reducing cofactor. The enzyme was formerly listed as EC 1.6.2.1.
Visual impairments limiting one or more of the basic functions of the eye: visual acuity, dark adaptation, color vision, or peripheral vision. These may result from EYE DISEASES; OPTIC NERVE DISEASES; VISUAL PATHWAY diseases; OCCIPITAL LOBE diseases; OCULAR MOTILITY DISORDERS; and other conditions (From Newell, Ophthalmology: Principles and Concepts, 7th ed, p132).
An autoimmune disorder of the EYE, occurring in patients with Graves disease. Subtypes include congestive (inflammation of the orbital connective tissue), myopathic (swelling and dysfunction of the extraocular muscles), and mixed congestive-myopathic ophthalmopathy.
An ocular disease, occurring in many forms, having as its primary characteristics an unstable or a sustained increase in the intraocular pressure which the eye cannot withstand without damage to its structure or impairment of its function. The consequences of the increased pressure may be manifested in a variety of symptoms, depending upon type and severity, such as excavation of the optic disk, hardness of the eyeball, corneal anesthesia, reduced visual acuity, seeing of colored halos around lights, disturbed dark adaptation, visual field defects, and headaches. (Dictionary of Visual Science, 4th ed)
The pressure of the fluids in the eye.
Bony cavity that holds the eyeball and its associated tissues and appendages.
The inability to see or the loss or absence of perception of visual stimuli. This condition may be the result of EYE DISEASES; OPTIC NERVE DISEASES; OPTIC CHIASM diseases; or BRAIN DISEASES affecting the VISUAL PATHWAYS or OCCIPITAL LOBE.
Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.
Method of measuring and mapping the scope of vision, from central to peripheral of each eye.
The percent frequency with which a dominant or homozygous recessive gene or gene combination manifests itself in the phenotype of the carriers. (From Glossary of Genetics, 5th ed)
A group of inherited disorders characterized by degeneration of dorsal root and autonomic ganglion cells, and clinically by loss of sensation and autonomic dysfunction. There are five subtypes. Type I features autosomal dominant inheritance and distal sensory involvement. Type II is characterized by autosomal inheritance and distal and proximal sensory loss. Type III is DYSAUTONOMIA, FAMILIAL. Type IV features insensitivity to pain, heat intolerance, and mental deficiency. Type V is characterized by a selective loss of pain with intact light touch and vibratory sensation. (From Joynt, Clinical Neurology, 1995, Ch51, pp142-4)
Conditions which affect the structure or function of the pupil of the eye, including disorders of innervation to the pupillary constrictor or dilator muscles, and disorders of pupillary reflexes.
Glaucoma in which the angle of the anterior chamber is open and the trabecular meshwork does not encroach on the base of the iris.
The electric response evoked in the cerebral cortex by visual stimulation or stimulation of the visual pathways.
The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.
Diseases of multiple peripheral nerves simultaneously. Polyneuropathies usually are characterized by symmetrical, bilateral distal motor and sensory impairment with a graded increase in severity distally. The pathological processes affecting peripheral nerves include degeneration of the axon, myelin or both. The various forms of polyneuropathy are categorized by the type of nerve affected (e.g., sensory, motor, or autonomic), by the distribution of nerve injury (e.g., distal vs. proximal), by nerve component primarily affected (e.g., demyelinating vs. axonal), by etiology, or by pattern of inheritance.
A branch of the tibial nerve which supplies sensory innervation to parts of the lower leg and foot.
Optic disk bodies composed primarily of acid mucopolysaccharides that may produce pseudopapilledema (elevation of the optic disk without associated INTRACRANIAL HYPERTENSION) and visual field deficits. Drusen may also occur in the retina (see RETINAL DRUSEN). (Miller et al., Clinical Neuro-Ophthalmology, 4th ed, p355)
Diseases caused by abnormal function of the MITOCHONDRIA. They may be caused by mutations, acquired or inherited, in mitochondrial DNA or in nuclear genes that code for mitochondrial components. They may also be the result of acquired mitochondria dysfunction due to adverse effects of drugs, infections, or other environmental causes.
Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.
Mechanical compression of nerves or nerve roots from internal or external causes. These may result in a conduction block to nerve impulses (due to MYELIN SHEATH dysfunction) or axonal loss. The nerve and nerve sheath injuries may be caused by ISCHEMIA; INFLAMMATION; or a direct mechanical effect.
The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
Visualization of a vascular system after intravenous injection of a fluorescein solution. The images may be photographed or televised. It is used especially in studying the retinal and uveal vasculature.
In invertebrate zoology, a lateral lobe of the FOREBRAIN in certain ARTHROPODS. In vertebrate zoology, either of the corpora bigemina of non-mammalian VERTEBRATES. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1329)
The concave interior of the eye, consisting of the retina, the choroid, the sclera, the optic disk, and blood vessels, seen by means of the ophthalmoscope. (Cline et al., Dictionary of Visual Science, 4th ed)
The continuous visual field seen by a subject through space and time.
A systemic autoimmune disorder that typically affects medium and large ARTERIES, usually leading to occlusive granulomatous vasculitis with transmural infiltrate containing multinucleated GIANT CELLS. The TEMPORAL ARTERY is commonly involved. This disorder appears primarily in people over the age of 50. Symptoms include FEVER; FATIGUE; HEADACHE; visual impairment; pain in the jaw and tongue; and aggravation of pain by cold temperatures. (From Adams et al., Principles of Neurology, 6th ed)
An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.
Disease involving the ULNAR NERVE from its origin in the BRACHIAL PLEXUS to its termination in the hand. Clinical manifestations may include PARESIS or PARALYSIS of wrist flexion, finger flexion, thumb adduction, finger abduction, and finger adduction. Sensation over the medial palm, fifth finger, and ulnar aspect of the ring finger may also be impaired. Common sites of injury include the AXILLA, cubital tunnel at the ELBOW, and Guyon's canal at the wrist. (From Joynt, Clinical Neurology, 1995, Ch51 pp43-5)
Method of making images on a sensitized surface by exposure to light or other radiant energy.
A hereditary motor and sensory neuropathy transmitted most often as an autosomal dominant trait and characterized by progressive distal wasting and loss of reflexes in the muscles of the legs (and occasionally involving the arms). Onset is usually in the second to fourth decade of life. This condition has been divided into two subtypes, hereditary motor and sensory neuropathy (HMSN) types I and II. HMSN I is associated with abnormal nerve conduction velocities and nerve hypertrophy, features not seen in HMSN II. (Adams et al., Principles of Neurology, 6th ed, p1343)
Sudden ISCHEMIA in the RETINA due to blocked blood flow through the CENTRAL RETINAL ARTERY or its branches leading to sudden complete or partial loss of vision, respectively, in the eye.
Methods and procedures for the diagnosis of diseases of the eye or of vision disorders.
A surgical operation for the relief of pressure in a body compartment or on a body part. (From Dorland, 28th ed)
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
A specialized field of physics and engineering involved in studying the behavior and properties of light and the technology of analyzing, generating, transmitting, and manipulating ELECTROMAGNETIC RADIATION in the visible, infrared, and ultraviolet range.
Diseases of the parasympathetic or sympathetic divisions of the AUTONOMIC NERVOUS SYSTEM; which has components located in the CENTRAL NERVOUS SYSTEM and PERIPHERAL NERVOUS SYSTEM. Autonomic dysfunction may be associated with HYPOTHALAMIC DISEASES; BRAIN STEM disorders; SPINAL CORD DISEASES; and PERIPHERAL NERVOUS SYSTEM DISEASES. Manifestations include impairments of vegetative functions including the maintenance of BLOOD PRESSURE; HEART RATE; pupil function; SWEATING; REPRODUCTIVE AND URINARY PHYSIOLOGY; and DIGESTION.
Glial cell derived tumors arising from the optic nerve, usually presenting in childhood.
INFLAMMATION of any ARTERIES.
A condition where damage to the peripheral nervous system (including the peripheral elements of the autonomic nervous system) is associated with chronic ingestion of alcoholic beverages. The disorder may be caused by a direct effect of alcohol, an associated nutritional deficiency, or a combination of factors. Clinical manifestations include variable degrees of weakness; ATROPHY; PARESTHESIAS; pain; loss of reflexes; sensory loss; diaphoresis; and postural hypotension. (From Arch Neurol 1995;52(1):45-51; Adams et al., Principles of Neurology, 6th ed, p1146)
Examination of the interior of the eye with an ophthalmoscope.
Retinal diseases refer to a diverse group of vision-threatening disorders that affect the retina's structure and function, including age-related macular degeneration, diabetic retinopathy, retinal detachment, retinitis pigmentosa, and macular edema, among others.
Three groups of arteries found in the eye which supply the iris, pupil, sclera, conjunctiva, and the muscles of the iris.
The numerous (6-12) small thin-walled spaces or air cells in the ETHMOID BONE located between the eyes. These air cells form an ethmoidal labyrinth.
A condition in which the intraocular pressure is elevated above normal and which may lead to glaucoma.
Biochemical identification of mutational changes in a nucleotide sequence.
A flavoprotein and iron sulfur-containing oxidoreductase complex that catalyzes the conversion of UBIQUINONE to ubiquinol. In MITOCHONDRIA the complex also couples its reaction to the transport of PROTONS across the internal mitochondrial membrane. The NADH DEHYDROGENASE component of the complex can be isolated and is listed as EC 1.6.99.3.
The organ of sight constituting a pair of globular organs made up of a three-layered roughly spherical structure specialized for receiving and responding to light.
A visual symptom in which a single object is perceived by the visual cortex as two objects rather than one. Disorders associated with this condition include REFRACTIVE ERRORS; STRABISMUS; OCULOMOTOR NERVE DISEASES; TROCHLEAR NERVE DISEASES; ABDUCENS NERVE DISEASES; and diseases of the BRAIN STEM and OCCIPITAL LOBE.
A localized defect in the visual field bordered by an area of normal vision. This occurs with a variety of EYE DISEASES (e.g., RETINAL DISEASES and GLAUCOMA); OPTIC NERVE DISEASES, and other conditions.
Diseases characterized by loss or dysfunction of myelin in the central or peripheral nervous system.
A mutation caused by the substitution of one nucleotide for another. This results in the DNA molecule having a change in a single base pair.
Diseases affecting the eye.
An antitubercular agent that inhibits the transfer of mycolic acids into the cell wall of the tubercle bacillus. It may also inhibit the synthesis of spermidine in mycobacteria. The action is usually bactericidal, and the drug can penetrate human cell membranes to exert its lethal effect. (From Smith and Reynard, Textbook of Pharmacology, 1992, p863)
Defects of color vision are mainly hereditary traits but can be secondary to acquired or developmental abnormalities in the CONES (RETINA). Severity of hereditary defects of color vision depends on the degree of mutation of the ROD OPSINS genes (on X CHROMOSOME and CHROMOSOME 3) that code the photopigments for red, green and blue.
Loss of functional activity and trophic degeneration of nerve axons and their terminal arborizations following the destruction of their cells of origin or interruption of their continuity with these cells. The pathology is characteristic of neurodegenerative diseases. Often the process of nerve degeneration is studied in research on neuroanatomical localization and correlation of the neurophysiology of neural pathways.
Disease involving the femoral nerve. The femoral nerve may be injured by ISCHEMIA (e.g., in association with DIABETIC NEUROPATHIES), nerve compression, trauma, COLLAGEN DISEASES, and other disease processes. Clinical features include MUSCLE WEAKNESS or PARALYSIS of hip flexion and knee extension, ATROPHY of the QUADRICEPS MUSCLE, reduced or absent patellar reflex, and impaired sensation over the anterior and medial thigh.
Enzymes that hydrolyze GTP to GDP. EC 3.6.1.-.
Partial or complete loss of vision in one half of the visual field(s) of one or both eyes. Subtypes include altitudinal hemianopsia, characterized by a visual defect above or below the horizontal meridian of the visual field. Homonymous hemianopsia refers to a visual defect that affects both eyes equally, and occurs either to the left or right of the midline of the visual field. Binasal hemianopsia consists of loss of vision in the nasal hemifields of both eyes. Bitemporal hemianopsia is the bilateral loss of vision in the temporal fields. Quadrantanopsia refers to loss of vision in one quarter of the visual field in one or both eyes.
Inflammation in which both the anterior and posterior segments of the uvea are involved and a specific focus is not apparent. It is often severe and extensive and a serious threat to vision. Causes include systemic diseases such as tuberculosis, sarcoidosis, and syphilis, as well as malignancies. The intermediate segment of the eye is not involved.
Measurement of ocular tension (INTRAOCULAR PRESSURE) with a tonometer. (Cline, et al., Dictionary of Visual Science, 4th ed)
Inflammation of the choroid.
A retention cyst of the salivary gland, lacrimal sac, paranasal sinuses, appendix, or gallbladder. (Stedman, 26th ed)
Recording of electric potentials in the retina after stimulation by light.
A bright bluish pink compound that has been used as a dye, biological stain, and diagnostic aid.
Genes that are located on the MITOCHONDRIAL DNA. Mitochondrial inheritance is often referred to as maternal inheritance but should be differentiated from maternal inheritance that is transmitted chromosomally.
Disease involving the median nerve, from its origin at the BRACHIAL PLEXUS to its termination in the hand. Clinical features include weakness of wrist and finger flexion, forearm pronation, thenar abduction, and loss of sensation over the lateral palm, first three fingers, and radial half of the ring finger. Common sites of injury include the elbow, where the nerve passes through the two heads of the pronator teres muscle (pronator syndrome) and in the carpal tunnel (CARPAL TUNNEL SYNDROME).
DNA probes specific for the human leukocyte antigen genes, which represent the major histocompatibility determinants in humans. The four known loci are designated as A, B, C, and D. Specific antigens are identified by a locus notation and number, e.g., HLA-A11. The inheritance of certain HLA alleles is associated with increased risk for certain diseases (e.g., insulin-dependent diabetes mellitus).
The nerves outside of the brain and spinal cord, including the autonomic, cranial, and spinal nerves. Peripheral nerves contain non-neuronal cells and connective tissue as well as axons. The connective tissue layers include, from the outside to the inside, the epineurium, the perineurium, and the endoneurium.
Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
Vision considered to be inferior to normal vision as represented by accepted standards of acuity, field of vision, or motility. Low vision generally refers to visual disorders that are caused by diseases that cannot be corrected by refraction (e.g., MACULAR DEGENERATION; RETINITIS PIGMENTOSA; DIABETIC RETINOPATHY, etc.).
Surgery performed on the eye or any of its parts.
A syndrome characterized by acute OPTIC NEURITIS; MYELITIS, TRANSVERSE; demyelinating and/or necrotizing lesions in the OPTIC NERVES and SPINAL CORD; and presence of specific autoantibodies to AQUAPORIN 4.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
Disorders of the peripheral nervous system associated with the deposition of AMYLOID in nerve tissue. Familial, primary (nonfamilial), and secondary forms have been described. Some familial subtypes demonstrate an autosomal dominant pattern of inheritance. Clinical manifestations include sensory loss, mild weakness, autonomic dysfunction, and CARPAL TUNNEL SYNDROME. (Adams et al., Principles of Neurology, 6th ed, p1349)
A common form of hyperthyroidism with a diffuse hyperplastic GOITER. It is an autoimmune disorder that produces antibodies against the THYROID STIMULATING HORMONE RECEPTOR. These autoantibodies activate the TSH receptor, thereby stimulating the THYROID GLAND and hypersecretion of THYROID HORMONES. These autoantibodies can also affect the eyes (GRAVES OPHTHALMOPATHY) and the skin (Graves dermopathy).
Abnormal protrusion of both eyes; may be caused by endocrine gland malfunction, malignancy, injury, or paralysis of the extrinsic muscles of the eye.
A hypoperfusion of the BLOOD through an organ or tissue caused by a PATHOLOGIC CONSTRICTION or obstruction of its BLOOD VESSELS, or an absence of BLOOD CIRCULATION.
Diseases affecting or involving the PARANASAL SINUSES and generally manifesting as inflammation, abscesses, cysts, or tumors.
Formation of an infarct, which is NECROSIS in tissue due to local ISCHEMIA resulting from obstruction of BLOOD CIRCULATION, most commonly by a THROMBUS or EMBOLUS.
Disorders of one or more of the twelve cranial nerves. With the exception of the optic and olfactory nerves, this includes disorders of the brain stem nuclei from which the cranial nerves originate or terminate.
The genetic constitution of individuals with respect to one member of a pair of allelic genes, or sets of genes that are closely linked and tend to be inherited together such as those of the MAJOR HISTOCOMPATIBILITY COMPLEX.
Arteries arising from the external carotid or the maxillary artery and distributing to the temporal region.
Set of cell bodies and nerve fibers conducting impulses from the eyes to the cerebral cortex. It includes the RETINA; OPTIC NERVE; optic tract; and geniculocalcarine tract.
A nerve which originates in the lumbar and sacral spinal cord (L4 to S3) and supplies motor and sensory innervation to the lower extremity. The sciatic nerve, which is the main continuation of the sacral plexus, is the largest nerve in the body. It has two major branches, the TIBIAL NERVE and the PERONEAL NERVE.
A form of glaucoma in which the intraocular pressure increases because the angle of the anterior chamber is blocked and the aqueous humor cannot drain from the anterior chamber.
Type of vision test used to determine COLOR VISION DEFECTS.
An autoimmune disorder mainly affecting young adults and characterized by destruction of myelin in the central nervous system. Pathologic findings include multiple sharply demarcated areas of demyelination throughout the white matter of the central nervous system. Clinical manifestations include visual loss, extra-ocular movement disorders, paresthesias, loss of sensation, weakness, dysarthria, spasticity, ataxia, and bladder dysfunction. The usual pattern is one of recurrent attacks followed by partial recovery (see MULTIPLE SCLEROSIS, RELAPSING-REMITTING), but acute fulminating and chronic progressive forms (see MULTIPLE SCLEROSIS, CHRONIC PROGRESSIVE) also occur. (Adams et al., Principles of Neurology, 6th ed, p903)
A form of GLAUCOMA in which chronic optic nerve damage and loss of vision normally attributable to buildup of intraocular pressure occurs despite prevailing conditions of normal intraocular pressure.
A dull or sharp painful sensation associated with the outer or inner structures of the eyeball, having different causes.
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
Ulnar neuropathies caused by mechanical compression of the nerve at any location from its origin at the BRACHIAL PLEXUS to its terminations in the hand. Common sites of compression include the retroepicondylar groove, cubital tunnel at the elbow (CUBITAL TUNNEL SYNDROME), and Guyon's canal at the wrist. Clinical features depend on the site of injury, but may include weakness or paralysis of wrist flexion, finger flexion, and ulnar innervated intrinsic hand muscles, and impaired sensation over the ulnar aspect of the hand, fifth finger, and ulnar half of the ring finger. (Joynt, Clinical Neurology, 1995, Ch51, p43)
The administration of substances into the VITREOUS BODY of the eye with a hypodermic syringe.
Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.
The age, developmental stage, or period of life at which a disease or the initial symptoms or manifestations of a disease appear in an individual.
Involuntary movements of the eye that are divided into two types, jerk and pendular. Jerk nystagmus has a slow phase in one direction followed by a corrective fast phase in the opposite direction, and is usually caused by central or peripheral vestibular dysfunction. Pendular nystagmus features oscillations that are of equal velocity in both directions and this condition is often associated with visual loss early in life. (Adams et al., Principles of Neurology, 6th ed, p272)
Diagnosis of disease states by recording the spontaneous electrical activity of tissues or organs or by the response to stimulation of electrically excitable tissue.
Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.
Artery originating from the internal carotid artery and distributing to the eye, orbit and adjacent facial structures.
A lipid-soluble benzoquinone which is involved in ELECTRON TRANSPORT in mitochondrial preparations. The compound occurs in the majority of aerobic organisms, from bacteria to higher plants and animals.
An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting POTASSIUM CHANNELS and VOLTAGE-GATED SODIUM CHANNELS. There is a resulting decrease in heart rate and in vascular resistance.
Diseases of the central and peripheral nervous system. This includes disorders of the brain, spinal cord, cranial nerves, peripheral nerves, nerve roots, autonomic nervous system, neuromuscular junction, and muscle.
Individuals whose ancestral origins are in the southeastern and eastern areas of the Asian continent.
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
The aperture in the iris through which light passes.
Methods and procedures for the diagnosis of diseases of the nervous system, central and peripheral, or demonstration of neurologic function or dysfunction.
Inflammation of the NASAL MUCOSA in the ETHMOID SINUS. It may present itself as an acute (infectious) or chronic (allergic) condition.
Examination of the angle of the anterior chamber of the eye with a specialized optical instrument (gonioscope) or a contact prism lens.
The anterior pair of the quadrigeminal bodies which coordinate the general behavioral orienting responses to visual stimuli, such as whole-body turning, and reaching.
Ocular manifestations secondary to various NEOPLASMS in which antibodies to antigens of the primary tumor cross-react with ocular antigens. This autoimmune response often leads to visual loss and other ocular dysfunctions.
Pipecolic acids are cyclic amino acids, specifically a derivative of L-lysine, that can function as an indicator of certain metabolic disorders such as lysinuric protein intolerance and maple syrup urine disease.
Type III intermediate filament proteins that assemble into neurofilaments, the major cytoskeletal element in nerve axons and dendrites. They consist of three distinct polypeptides, the neurofilament triplet. Types I, II, and IV intermediate filament proteins form other cytoskeletal elements such as keratins and lamins. It appears that the metabolism of neurofilaments is disturbed in Alzheimer's disease, as indicated by the presence of neurofilament epitopes in the neurofibrillary tangles, as well as by the severe reduction of the expression of the gene for the light neurofilament subunit of the neurofilament triplet in brains of Alzheimer's patients. (Can J Neurol Sci 1990 Aug;17(3):302)
The cellular processes involved in adjustments to the MITOCHONDRIAL VOLUME, content, and activity, that depend on the energy demands of the cell.
STILBENES with AMIDINES attached.
Derivatives of acetamide that are used as solvents, as mild irritants, and in organic synthesis.
A botanical insecticide that is an inhibitor of mitochondrial electron transport.
Subjective cutaneous sensations (e.g., cold, warmth, tingling, pressure, etc.) that are experienced spontaneously in the absence of stimulation.
Disease involving the common PERONEAL NERVE or its branches, the deep and superficial peroneal nerves. Lesions of the deep peroneal nerve are associated with PARALYSIS of dorsiflexion of the ankle and toes and loss of sensation from the web space between the first and second toe. Lesions of the superficial peroneal nerve result in weakness or paralysis of the peroneal muscles (which evert the foot) and loss of sensation over the dorsal and lateral surface of the leg. Traumatic injury to the common peroneal nerve near the head of the FIBULA is a relatively common cause of this condition. (From Joynt, Clinical Neurology, 1995, Ch51, p31)
The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.
Derivatives of oxazolidin-2-one. They represent an important class of synthetic antibiotic agents.
The technology of transmitting light over long distances through strands of glass or other transparent material.
Disorders of the special senses (i.e., VISION; HEARING; TASTE; and SMELL) or somatosensory system (i.e., afferent components of the PERIPHERAL NERVOUS SYSTEM).
That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants.
The worsening of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.
An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.
The lipid-rich sheath surrounding AXONS in both the CENTRAL NERVOUS SYSTEMS and PERIPHERAL NERVOUS SYSTEM. The myelin sheath is an electrical insulator and allows faster and more energetically efficient conduction of impulses. The sheath is formed by the cell membranes of glial cells (SCHWANN CELLS in the peripheral and OLIGODENDROGLIA in the central nervous system). Deterioration of the sheath in DEMYELINATING DISEASES is a serious clinical problem.
A flavoprotein that reversibly catalyzes the oxidation of NADH or NADPH by various quinones and oxidation-reduction dyes. The enzyme is inhibited by dicoumarol, capsaicin, and caffeine.
Elements of limited time intervals, contributing to particular results or situations.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
Disease having a short and relatively severe course.
The therapeutic intermittent administration of oxygen in a chamber at greater than sea-level atmospheric pressures (three atmospheres). It is considered effective treatment for air and gas embolisms, smoke inhalation, acute carbon monoxide poisoning, caisson disease, clostridial gangrene, etc. (From Segen, Dictionary of Modern Medicine, 1992). The list of treatment modalities includes stroke.
Hearing loss due to disease of the AUDITORY PATHWAYS (in the CENTRAL NERVOUS SYSTEM) which originate in the COCHLEAR NUCLEI of the PONS and then ascend bilaterally to the MIDBRAIN, the THALAMUS, and then the AUDITORY CORTEX in the TEMPORAL LOBE. Bilateral lesions of the auditory pathways are usually required to cause central hearing loss. Cortical deafness refers to loss of hearing due to bilateral auditory cortex lesions. Unilateral BRAIN STEM lesions involving the cochlear nuclei may result in unilateral hearing loss.
Mental processing of chromatic signals (COLOR VISION) from the eye by the VISUAL CORTEX where they are converted into symbolic representations. Color perception involves numerous neurons, and is influenced not only by the distribution of wavelengths from the viewed object, but also by its background color and brightness contrast at its boundary.
Inbreed BN (Brown Norway) rats are a strain of laboratory rats that are specifically bred for research purposes, characterized by their uniform genetic makeup and susceptibility to various diseases, which makes them ideal models for studying human physiology and pathophysiology.
An individual having different alleles at one or more loci regarding a specific character.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
Traumatic injuries to the cranium where the integrity of the skull is not compromised and no bone fragments or other objects penetrate the skull and dura mater. This frequently results in mechanical injury being transmitted to intracranial structures which may produce traumatic brain injuries, hemorrhage, or cranial nerve injury. (From Rowland, Merritt's Textbook of Neurology, 9th ed, p417)
The muscles that move the eye. Included in this group are the medial rectus, lateral rectus, superior rectus, inferior rectus, inferior oblique, superior oblique, musculus orbitalis, and levator palpebrae superioris.
The number of CELLS of a specific kind, usually measured per unit volume or area of sample.
A major nerve of the upper extremity. In humans, the fibers of the ulnar nerve originate in the lower cervical and upper thoracic spinal cord (usually C7 to T1), travel via the medial cord of the brachial plexus, and supply sensory and motor innervation to parts of the hand and forearm.
Electron transfer through the cytochrome system liberating free energy which is transformed into high-energy phosphate bonds.
Images seen by one eye.
A class of large neuroglial (macroglial) cells in the central nervous system - the largest and most numerous neuroglial cells in the brain and spinal cord. Astrocytes (from "star" cells) are irregularly shaped with many long processes, including those with "end feet" which form the glial (limiting) membrane and directly and indirectly contribute to the BLOOD-BRAIN BARRIER. They regulate the extracellular ionic and chemical environment, and "reactive astrocytes" (along with MICROGLIA) respond to injury.
Diseases characterized by a selective degeneration of the motor neurons of the spinal cord, brainstem, or motor cortex. Clinical subtypes are distinguished by the major site of degeneration. In AMYOTROPHIC LATERAL SCLEROSIS there is involvement of upper, lower, and brainstem motor neurons. In progressive muscular atrophy and related syndromes (see MUSCULAR ATROPHY, SPINAL) the motor neurons in the spinal cord are primarily affected. With progressive bulbar palsy (BULBAR PALSY, PROGRESSIVE), the initial degeneration occurs in the brainstem. In primary lateral sclerosis, the cortical neurons are affected in isolation. (Adams et al., Principles of Neurology, 6th ed, p1089)
An intermediate filament protein found only in glial cells or cells of glial origin. MW 51,000.
A form of fluorescent antibody technique commonly used to detect serum antibodies and immune complexes in tissues and microorganisms in specimens from patients with infectious diseases. The technique involves formation of an antigen-antibody complex which is labeled with fluorescein-conjugated anti-immunoglobulin antibody. (From Bennington, Saunders Dictionary & Encyclopedia of Laboratory Medicine and Technology, 1984)
A self-limiting bacterial infection of the regional lymph nodes caused by AFIPIA felis, a gram-negative bacterium recently identified by the Centers for Disease Control and Prevention and by BARTONELLA HENSELAE. It usually arises one or more weeks following a feline scratch, with raised inflammatory nodules at the site of the scratch being the primary symptom.
Identification of genetic carriers for a given trait.
Harmful effects of non-experimental exposure to ionizing or non-ionizing radiation in VERTEBRATES.
Diseases characterized by injury or dysfunction involving multiple peripheral nerves and nerve roots. The process may primarily affect myelin or nerve axons. Two of the more common demyelinating forms are acute inflammatory polyradiculopathy (GUILLAIN-BARRE SYNDROME) and POLYRADICULONEUROPATHY, CHRONIC INFLAMMATORY DEMYELINATING. Polyradiculoneuritis refers to inflammation of multiple peripheral nerves and spinal nerve roots.
'Eye proteins' are structural or functional proteins, such as crystallins, opsins, and collagens, located in various parts of the eye, including the cornea, lens, retina, and aqueous humor, that contribute to maintaining transparency, refractive power, phototransduction, and overall integrity of the visual system.
Inherited disorders of the peripheral nervous system associated with the deposition of AMYLOID in nerve tissue. The different clinical types based on symptoms correspond to the presence of a variety of mutations in several different proteins including transthyretin (PREALBUMIN); APOLIPOPROTEIN A-I; and GELSOLIN.
Congenital anomaly in which some of the structures of the eye are absent due to incomplete fusion of the fetal intraocular fissure during gestation.
A mutation in which a codon is mutated to one directing the incorporation of a different amino acid. This substitution may result in an inactive or unstable product. (From A Dictionary of Genetics, King & Stansfield, 5th ed)
A protein that accounts for more than half of the peripheral nervous system myelin protein. The extracellular domain of this protein is believed to engage in adhesive interactions and thus hold the myelin membrane compact. It can behave as a homophilic adhesion molecule through interactions with its extracellular domains. (From J Cell Biol 1994;126(4):1089-97)
Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.
Disease of the TIBIAL NERVE (also referred to as the posterior tibial nerve). The most commonly associated condition is the TARSAL TUNNEL SYNDROME. However, LEG INJURIES; ISCHEMIA; and inflammatory conditions (e.g., COLLAGEN DISEASES) may also affect the nerve. Clinical features include PARALYSIS of plantar flexion, ankle inversion and toe flexion as well as loss of sensation over the sole of the foot. (From Joynt, Clinical Neurology, 1995, Ch51, p32)
A diffuse or multifocal peripheral neuropathy related to the remote effects of a neoplasm, most often carcinoma or lymphoma. Pathologically, there are inflammatory changes in peripheral nerves. The most common clinical presentation is a symmetric distal mixed sensorimotor polyneuropathy. (Adams et al., Principles of Neurology, 6th ed, p1334)
Assessment of sensory and motor responses and reflexes that is used to determine impairment of the nervous system.
Photosensitive proteins expressed in the ROD PHOTORECEPTOR CELLS. They are the protein components of rod photoreceptor pigments such as RHODOPSIN.
Intense or aching pain that occurs along the course or distribution of a peripheral or cranial nerve.
Pathological processes of the VESTIBULOCOCHLEAR NERVE, including the branches of COCHLEAR NERVE and VESTIBULAR NERVE. Common examples are VESTIBULAR NEURITIS, cochlear neuritis, and ACOUSTIC NEUROMA. Clinical signs are varying degree of HEARING LOSS; VERTIGO; and TINNITUS.
A group of CORTICOSTEROIDS that affect carbohydrate metabolism (GLUCONEOGENESIS, liver glycogen deposition, elevation of BLOOD SUGAR), inhibit ADRENOCORTICOTROPIC HORMONE secretion, and possess pronounced anti-inflammatory activity. They also play a role in fat and protein metabolism, maintenance of arterial blood pressure, alteration of the connective tissue response to injury, reduction in the number of circulating lymphocytes, and functioning of the central nervous system.
MYELIN-specific proteins that play a structural or regulatory role in the genesis and maintenance of the lamellar MYELIN SHEATH structure.
Disease or damage involving the SCIATIC NERVE, which divides into the PERONEAL NERVE and TIBIAL NERVE (see also PERONEAL NEUROPATHIES and TIBIAL NEUROPATHY). Clinical manifestations may include SCIATICA or pain localized to the hip, PARESIS or PARALYSIS of posterior thigh muscles and muscles innervated by the peroneal and tibial nerves, and sensory loss involving the lateral and posterior thigh, posterior and lateral leg, and sole of the foot. The sciatic nerve may be affected by trauma; ISCHEMIA; COLLAGEN DISEASES; and other conditions. (From Adams et al., Principles of Neurology, 6th ed, p1363)
An acute inflammatory autoimmune neuritis caused by T cell- mediated cellular immune response directed towards peripheral myelin. Demyelination occurs in peripheral nerves and nerve roots. The process is often preceded by a viral or bacterial infection, surgery, immunization, lymphoma, or exposure to toxins. Common clinical manifestations include progressive weakness, loss of sensation, and loss of deep tendon reflexes. Weakness of respiratory muscles and autonomic dysfunction may occur. (From Adams et al., Principles of Neurology, 6th ed, pp1312-1314)
'Mandibular diseases' refer to various medical conditions that primarily affect the structure, function, or health of the mandible (lower jawbone), including but not limited to infections, tumors, developmental disorders, and degenerative diseases.
The termination of the cell's ability to carry out vital functions such as metabolism, growth, reproduction, responsiveness, and adaptability.
Common foot problems in persons with DIABETES MELLITUS, caused by any combination of factors such as DIABETIC NEUROPATHIES; PERIPHERAL VASCULAR DISEASES; and INFECTION. With the loss of sensation and poor circulation, injuries and infections often lead to severe foot ulceration, GANGRENE and AMPUTATION.
The ability to detect sharp boundaries (stimuli) and to detect slight changes in luminance at regions without distinct contours. Psychophysical measurements of this visual function are used to evaluate visual acuity and to detect eye disease.
Drugs intended to prevent damage to the brain or spinal cord from ischemia, stroke, convulsions, or trauma. Some must be administered before the event, but others may be effective for some time after. They act by a variety of mechanisms, but often directly or indirectly minimize the damage produced by endogenous excitatory amino acids.
Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The lateral of the two terminal branches of the sciatic nerve. The peroneal (or fibular) nerve provides motor and sensory innervation to parts of the leg and foot.
The nervous system outside of the brain and spinal cord. The peripheral nervous system has autonomic and somatic divisions. The autonomic nervous system includes the enteric, parasympathetic, and sympathetic subdivisions. The somatic nervous system includes the cranial and spinal nerves and their ganglia and the peripheral sensory receptors.
A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
Tomography using x-ray transmission and a computer algorithm to reconstruct the image.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
Neuroglial cells of the peripheral nervous system which form the insulating myelin sheaths of peripheral axons.
Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.

Fluorescein angiographic features of choroidal insufficiency in anterior ischemic optic neuropathy. (1/142)

Anterior ischemic optic neuropathy(AION) is known to be caused by circulatory disturbance in the anterior optic nerve(AON). Because the AON shares blood supply from the paraoptic short posterior ciliary artery with peripapillary choroid, the authors investigated the angiographic evidences of combined choroidal insufficiency in patients with acute AION. Fundus fluorescein angiograms from 30 eyes from 28 patients with acute AION were enrolled in this study. The diagnosis of acute AION was based primarily on angiographic evidences of filling delay of optic nerve head and the various clinical features, such as decreased visual acuity, visual field defects, afferent pupillary defect, and optic disc swelling. Angiographic evidences of combined choroidal filling delay were as follows: 1) circular or localized filling delay of peripapillary choroid in 15 eyes (50%), 2) generalized filling delay of posterior pole in 11 eyes (36.7%), 3) filling delay of unilateral choroid divided by watershed zone in 5 eyes (16.7%), and 4) choriocapillary filling delay in 10 eyes (33.3%). In this study, various types of choroidal insufficiency in patients with AION were observed, which helped us to differentiate AION from the other various diseases of the anterior optic nerve.  (+info)

A case of optic neuropathy treated by percutaneous trans-coronary angiography. (2/142)

There are many risk factors involved in the development of ischemic optic neuropathy such as diabetes mellitus, hypertension, arteriosclerosis, and vascular incompetence. Therefore, the treatment of ischemic optic neuropathy should not be solely based on proper diagnosis but should also involve a thorough and systemic investigation to identify those multifactorial possibilities, which may contribute to the pathogenesis of the disease. We report upon a patient who developed non-arteritic ischemic optic neuropathy following treatment of a sphenoethmoid mucocele, which lead to recovered vision and a satisfactory improvement of visual field defects, after percutaneous trans-coronary angiography with stent insertion of the coronary arteries.  (+info)

Variable pattern of visual recovery of Leber's hereditary optic neuropathy. (3/142)

AIMS: To investigate pattern of visual recovery of nine patients with Leber's hereditary optic neuropathy (LHON) and a mitochondrial DNA mutation at 11778. METHODS: Recovery was judged significant when a gain of two lines or more in the Landolt ring chart, 10 dB or more improvement of the mean deviation of static perimetry, or improvement of critical flicker frequency (CFF) over 35 Hz was shown. RESULTS: All three visual functions tested dramatically recovered in one patient. Two other patients exhibited isolated improvement of CFF or visual field, respectively. CONCLUSION: Partial improvement of visual function may be more widespread than previously recognised in LHON patients with the 11778 mutation.  (+info)

An interocular comparison of the multifocal VEP: a possible technique for detecting local damage to the optic nerve. (4/142)

PURPOSE: To develop a quantitative measure of local damage to the ganglion cells/optic nerve based on an interocular comparison of multifocal visual evoked potentials (mVEP). METHODS: Multifocal VEPs were recorded from both eyes of six normal subjects and four patients; each eye was stimulated separately. Two of the patients had glaucoma, one had ischemic optic neuropathy, and one had unilateral optic neuritis. All four patients had considerably more damage in one eye than in the other, as indicated by their Humphrey visual fields. The multi-input procedure of Sutter was used to obtain 60 VEP responses to a scaled checkerboard pattern. The amplitude in each response was obtained using a root mean square measure of response magnitude. For each of the 60 pairs of responses, a ratio between the amplitude of the responses from the two eyes was obtained as a measure of the relative health of one eye compared with the other. The mean and SD of this ratio measure for the control group were used to specify confidence intervals for each of the 60 locations. All patients had Humphrey 24-2 visual fields performed. To allow a comparison of the mVEPs to the visual fields, a procedure was developed for displaying the results of both tests on a common set of coordinates. RESULTS: Except for a small interocular difference in timing attributable to nasotemporal retinal differences, the pairs of mVEP responses from the two eyes of the control subjects were essentially identical. Many of the pairs of responses from the patients were significantly different. In general, there was reasonably good agreement with the Humphrey 24-2 visual field data. Although some regions with visual field defects were not detected in the mVEP due to small responses from the better eye, other abnormalities were detected that were hard to discern in the visual fields. CONCLUSIONS: Local monocular damage to the ganglion cell/optic nerve can be quantitatively measured by an interocular comparison of the mVEP.  (+info)

Histopathologic studies of ischemic optic neuropathy. (5/142)

PURPOSE: To define the histopathologic features of eyes in which a pathologic diagnosis of ischemic optic neuropathy had been made in the years 1951 through 1998. METHODS: The following data were documented: age of patient, race, sex, source of tissue, cause of death, clinical history, interval from loss of vision to death, enucleation, exenteration, and biopsy. The histopathologic criteria for diagnosis of ischemic optic neuropathy were the presence of localized ischemic edema, cavernous degeneration, or an area of atrophy located superior or inferior in the optic nerve. Cases with history of abrupt loss of vision were combined with reports from the literature to construct a time table of histopathologic features and associated conditions. RESULTS: Ischemic optic neuropathy was present in 193 eyes. There were 88 females and 65 males. The average age was 71.6 years. Ischemic edema without (early) and with (later) gitter macrophages was present in 26 (13.5%). Cavernous degeneration was present in 69 nerves (36%). Mucopolysaccharide (MPS) was present in 37 cavernous lesions 1 month or longer after loss of vision. Cavernous lesions were seen in 3 eyes in which peripapillary retinal nerve fiber layer hemorrhage had been observed prior to death. Atrophic lesions, the most common pattern, were observed in 133 optic nerves (66.8%). More than 1 ischemic lesion was seen in 38 optic nerves (19.7%). Bilateral ischemic lesions were seen in 50 (35.2%) of 142 paired eyes. CONCLUSIONS: Ischemic optic nerve lesions are initially acellular and later show macrophage infiltration. Cavernous lesions with MPS are present 4 weeks or longer after vision loss. The location of MPS posteriorly and along the internal margin suggests that MPS is produced at the edges of lesions. Progressive vision loss in ischemic optic neuropathy may be secondary to compression of intact nerve from ischemic edema and cavernous swelling, or a second ischemic lesion.  (+info)

Ischaemic optic neuropathy. (6/142)

Ischaemic optic neuropathy is of two types: anterior (AION) and posterior (PION), the first involving the optic nerve head (ONH) and the second, the rest of the optic nerve. Pathogenetically AION and PION are very different diseases. AION represents an acute ischaemic disorder of the ONH supplied by the posterior ciliary artery (PCA), while PION has no specific location in the posterior part of the optic nerve and does not represent an ischaemic disorder of any definite artery. The most important step towards a logical understanding of the underlying causes, clinical features, pathogenesis and rational management of AION, is to understand the basic scientific issues involved; these are discussed in some detail. AION clinically is of two types: (1) that due to giant cell arteritis (arteritic AION: A-AION) and (2) non-arteritic AION (NA-AION). NA-AION, the more common of the two, is one of the most prevalent and visually crippling diseases in the middle-aged and elderly, and is potentially bilateral. NA-AION is a multifactorial disease, with many risk factors collectively contributing to its development. Although there is no known treatment for NA-AION, reduction of risk factors is important in decreasing chances of involvement of the second eye and of further episodes. Our studies have suggested that nocturnal arterial hypotension is an important risk factor for the development and progression of NA-AION. The role of nocturnal arterial hypotension in the pathogenesis of NA-AION and management of nocturnal hypotension is discussed. Potent antihypertensive drugs, when used aggressively and/or given at bedtime, are emerging as an important risk factor for nocturnal hypotension, and there is some evidence that NA-AION may be occurring as an iatrogenic disease in some individuals. A-AION, by contrast, is an ocular emergency and requires immediate treatment with systemic corticosteroids to prevent further visual loss. The clinical parameters which help to differentiate the two types of AION, and their respective management are discussed.  (+info)

Hyperhomocyst(e)inaemia, but not MTHFR C677T mutation, as a risk factor for non-arteritic ischaemic optic neuropathy. (7/142)

BACKGROUND/AIMS: Hyperhomocyst(e)inaemia has been identified as a strong risk factor for stroke, myocardial infarction, and deep vein thrombosis. A point mutation of methylene tetrahydrofolate reductase (MTHFR C677T) has been associated with increased plasma homocyst(e)ine levels. To investigate whether hyperhomocyst(e)inaemia and/or MTHFR C677T mutation are associated with non-arteritic ischaemic optic neuropathy (NAION), a case-control study including 59 consecutive patients with NAION and 59 controls matched for age and sex was performed. METHODS: Fasting plasma homocyst(e)ine levels, MTHFR C677T genotypes, and plasma levels of folate and vitamin B-12 were determined. RESULTS: Mean plasma homocyst(e)ine levels were significantly higher in patients than in controls (11.8 (SD 5.7) micromol/l v 9.8 (2.5) micromol/l, p = 0.02). The odds ratio for patients with homocyst(e)ine levels exceeding the 95th percentile of control homocyst(e)ine levels was 5.8 (95% CI 1.5-21.4). Mean plasma folate levels were significantly lower in patients than in controls (4.3 (1.7) ng/ml v 5.5 (1.9) ng/ml, p = 0.001), whereas plasma vitamin B-12 levels did not differ significantly. Prevalence of the MTHFR C677T mutation was not significantly increased in patients with NAION compared with controls. CONCLUSION: These results suggest that hyperhomocyst(e)inaemia, but not MTHFR C677T mutation is associated with NAION. Determination of plasma homocyst(e)ine levels might be of diagnostic value in patients with NAION.  (+info)

Steroid management in giant cell arteritis. (8/142)

AIM: Ocular involvement in giant cell arteritis (GCA) is an ophthalmic emergency which, if untreated, can progress to permanent blindness. There is little evidence in the literature to support current protocols for the acute treatment of GCA with steroids. The authors sought to review the effects of intravenous and oral steroids in GCA. METHODS: This retrospective study reviewed the records of 100 consecutive patients with biopsy proved giant cell arteritis. 73 patients with visual loss who were treated at the Royal Victorian Eye and Ear Hospital (RVEEH) and St Vincent's Hospital were included in the final series. The authors studied the management of the patients in the first week after presentation, analysing types of treatment, dose, effect on visual acuity, and complications. RESULTS: All the patients except one had visual loss due to anterior ischaemic optic neuropathy (AION). 17 patients (23%) had bilateral eye involvement. Visual acuity improved in 21 of 73 patients (29%) by a mean of two Snellen chart lines after commencement of steroids. There was an increased likelihood of improved vision in the group who had intravenous steroids (40%) compared with those who received oral steroids (13%). In all except four patients (95%) vision remained stable at 1 month review. CONCLUSIONS: Prompt treatment of GCA with steroids leads to improvement of visual acuity in a significant number of cases. Intravenous steroids may offer a greater prospect of improvement compared with oral steroids. A prospective trial comparing intravenous with oral steroids is needed to validate these findings and would not expose elderly patients to unacceptable risks.  (+info)

Ischemic optic neuropathy (ION) is a medical condition that refers to the damage or death of the optic nerve due to insufficient blood supply. The optic nerve is responsible for transmitting visual information from the eye to the brain.

In ION, the blood vessels that supply the optic nerve become blocked or narrowed, leading to decreased blood flow and oxygen delivery to the nerve fibers. This results in inflammation, swelling, and ultimately, damage to the optic nerve. The damage can cause sudden, painless vision loss, often noticed upon waking up in the morning.

There are two types of ION: anterior ischemic optic neuropathy (AION) and posterior ischemic optic neuropathy (PION). AION affects the front part of the optic nerve, while PION affects the back part of the nerve. AION is further classified into arteritic and non-arteritic types, depending on whether it is caused by giant cell arteritis or not.

Risk factors for ION include age (most commonly occurring in people over 50), hypertension, diabetes, smoking, sleep apnea, and other cardiovascular diseases. Treatment options depend on the type and cause of ION and may include controlling underlying medical conditions, administering corticosteroids, or undergoing surgical procedures to improve blood flow.

Hereditary Optic Atrophy, Leber type (LOA) is a mitochondrial DNA-associated inherited condition that primarily affects the optic nerve and leads to vision loss. It is characterized by the degeneration of retinal ganglion cells and their axons, which make up the optic nerve. This results in bilateral, painless, and progressive visual deterioration, typically beginning in young adulthood (14-35 years).

Leber's hereditary optic atrophy is caused by mutations in the mitochondrial DNA (mtDNA) gene MT-ND4 or MT-ND6. The condition follows a maternal pattern of inheritance, meaning that it is passed down through the mother's lineage.

The onset of LOA usually occurs in one eye first, followed by the second eye within weeks to months. Central vision is initially affected, leading to blurriness and loss of visual acuity. Color vision may also be impaired. The progression of the condition generally stabilizes after a few months, but complete recovery of vision is unlikely.

Currently, there is no cure for Leber's hereditary optic atrophy. Treatment focuses on managing symptoms and providing visual rehabilitation to help affected individuals adapt to their visual impairment.

The optic nerve, also known as the second cranial nerve, is the nerve that transmits visual information from the retina to the brain. It is composed of approximately one million nerve fibers that carry signals related to vision, such as light intensity and color, from the eye's photoreceptor cells (rods and cones) to the visual cortex in the brain. The optic nerve is responsible for carrying this visual information so that it can be processed and interpreted by the brain, allowing us to see and perceive our surroundings. Damage to the optic nerve can result in vision loss or impairment.

Optic nerve diseases refer to a group of conditions that affect the optic nerve, which transmits visual information from the eye to the brain. These diseases can cause various symptoms such as vision loss, decreased visual acuity, changes in color vision, and visual field defects. Examples of optic nerve diseases include optic neuritis (inflammation of the optic nerve), glaucoma (damage to the optic nerve due to high eye pressure), optic nerve damage from trauma or injury, ischemic optic neuropathy (lack of blood flow to the optic nerve), and optic nerve tumors. Treatment for optic nerve diseases varies depending on the specific condition and may include medications, surgery, or lifestyle changes.

Hereditary optic atrophies (HOAs) are a group of genetic disorders that cause degeneration of the optic nerve, leading to vision loss. The optic nerve is responsible for transmitting visual information from the eye to the brain. In HOAs, this nerve degenerates over time, resulting in decreased visual acuity, color vision deficits, and sometimes visual field defects.

There are several types of HOAs, including dominant optic atrophy (DOA), Leber hereditary optic neuropathy (LHON), autosomal recessive optic atrophy (AROA), and Wolfram syndrome. Each type has a different inheritance pattern and is caused by mutations in different genes.

DOA is the most common form of HOA and is characterized by progressive vision loss that typically begins in childhood or early adulthood. It is inherited in an autosomal dominant manner, meaning that a child has a 50% chance of inheriting the disease-causing mutation from an affected parent.

LHON is a mitochondrial disorder that primarily affects males and is characterized by sudden, severe vision loss that typically occurs in young adulthood. It is caused by mutations in the mitochondrial DNA and is inherited maternally.

AROA is a rare form of HOA that is inherited in an autosomal recessive manner, meaning that both copies of the gene must be mutated to cause the disease. It typically presents in infancy or early childhood with progressive vision loss.

Wolfram syndrome is a rare genetic disorder that affects multiple organs, including the eyes, ears, and endocrine system. It is characterized by diabetes insipidus, diabetes mellitus, optic atrophy, and hearing loss. It is inherited in an autosomal recessive manner.

There is currently no cure for HOAs, but treatments such as low-vision aids and rehabilitation may help to manage the symptoms. Research is ongoing to develop new therapies for these disorders.

Diabetic neuropathies refer to a group of nerve disorders that are caused by diabetes. High blood sugar levels can injure nerves throughout the body, but diabetic neuropathies most commonly affect the nerves in the legs and feet.

There are four main types of diabetic neuropathies:

1. Peripheral neuropathy: This is the most common type of diabetic neuropathy. It affects the nerves in the legs and feet, causing symptoms such as numbness, tingling, burning, or shooting pain.
2. Autonomic neuropathy: This type of neuropathy affects the autonomic nerves, which control involuntary functions such as heart rate, blood pressure, digestion, and bladder function. Symptoms may include dizziness, fainting, digestive problems, sexual dysfunction, and difficulty regulating body temperature.
3. Proximal neuropathy: Also known as diabetic amyotrophy, this type of neuropathy affects the nerves in the hips, thighs, or buttocks, causing weakness, pain, and difficulty walking.
4. Focal neuropathy: This type of neuropathy affects a single nerve or group of nerves, causing symptoms such as weakness, numbness, or pain in the affected area. Focal neuropathies can occur anywhere in the body, but they are most common in the head, torso, and legs.

The risk of developing diabetic neuropathies increases with the duration of diabetes and poor blood sugar control. Other factors that may contribute to the development of diabetic neuropathies include genetics, age, smoking, and alcohol consumption.

The optic disk, also known as the optic nerve head, is the point where the optic nerve fibers exit the eye and transmit visual information to the brain. It appears as a pale, circular area in the back of the eye, near the center of the retina. The optic disk has no photoreceptor cells (rods and cones), so it is insensitive to light. It is an important structure to observe during eye examinations because changes in its appearance can indicate various ocular diseases or conditions, such as glaucoma, optic neuritis, or papilledema.

Optic atrophy is a medical term that refers to the degeneration and shrinkage (atrophy) of the optic nerve, which transmits visual information from the eye to the brain. This condition can result in various vision abnormalities, including loss of visual acuity, color vision deficiencies, and peripheral vision loss.

Optic atrophy can occur due to a variety of causes, such as:

* Traumatic injuries to the eye or optic nerve
* Glaucoma
* Optic neuritis (inflammation of the optic nerve)
* Ischemic optic neuropathy (reduced blood flow to the optic nerve)
* Compression or swelling of the optic nerve
* Hereditary or congenital conditions affecting the optic nerve
* Toxins and certain medications that can damage the optic nerve.

The diagnosis of optic atrophy typically involves a comprehensive eye examination, including visual acuity testing, refraction assessment, slit-lamp examination, and dilated funduscopic examination to evaluate the health of the optic nerve. In some cases, additional diagnostic tests such as visual field testing, optical coherence tomography (OCT), or magnetic resonance imaging (MRI) may be necessary to confirm the diagnosis and determine the underlying cause.

There is no specific treatment for optic atrophy, but addressing the underlying cause can help prevent further damage to the optic nerve. In some cases, vision rehabilitation may be recommended to help patients adapt to their visual impairment.

Optic neuritis is a medical condition characterized by inflammation and damage to the optic nerve, which transmits visual information from the eye to the brain. This condition can result in various symptoms such as vision loss, pain with eye movement, color vision disturbances, and pupillary abnormalities. Optic neuritis may occur in isolation or be associated with other underlying medical conditions, including multiple sclerosis, neuromyelitis optica, and autoimmune disorders. The diagnosis typically involves a comprehensive eye examination, including visual acuity testing, dilated funduscopic examination, and possibly imaging studies like MRI to evaluate the optic nerve and brain. Treatment options may include corticosteroids or other immunomodulatory therapies to reduce inflammation and prevent further damage to the optic nerve.

Optic nerve injuries refer to damages or trauma inflicted on the optic nerve, which is a crucial component of the visual system. The optic nerve transmits visual information from the retina to the brain, enabling us to see. Injuries to the optic nerve can result in various visual impairments, including partial or complete vision loss, decreased visual acuity, changes in color perception, and reduced field of view.

These injuries may occur due to several reasons, such as:

1. Direct trauma to the eye or head
2. Increased pressure inside the eye (glaucoma)
3. Optic neuritis, an inflammation of the optic nerve
4. Ischemia, or insufficient blood supply to the optic nerve
5. Compression from tumors or other space-occupying lesions
6. Intrinsic degenerative conditions affecting the optic nerve
7. Toxic exposure to certain chemicals or medications

Optic nerve injuries are diagnosed through a comprehensive eye examination, including visual acuity testing, slit-lamp examination, dilated fundus exam, and additional diagnostic tests like optical coherence tomography (OCT) and visual field testing. Treatment options vary depending on the cause and severity of the injury but may include medications, surgery, or vision rehabilitation.

Peripheral Nervous System (PNS) diseases, also known as Peripheral Neuropathies, refer to conditions that affect the functioning of the peripheral nervous system, which includes all the nerves outside the brain and spinal cord. These nerves transmit signals between the central nervous system (CNS) and the rest of the body, controlling sensations, movements, and automatic functions such as heart rate and digestion.

PNS diseases can be caused by various factors, including genetics, infections, toxins, metabolic disorders, trauma, or autoimmune conditions. The symptoms of PNS diseases depend on the type and extent of nerve damage but often include:

1. Numbness, tingling, or pain in the hands and feet
2. Muscle weakness or cramps
3. Loss of reflexes
4. Decreased sensation to touch, temperature, or vibration
5. Coordination problems and difficulty with balance
6. Sexual dysfunction
7. Digestive issues, such as constipation or diarrhea
8. Dizziness or fainting due to changes in blood pressure

Examples of PNS diseases include Guillain-Barre syndrome, Charcot-Marie-Tooth disease, diabetic neuropathy, and peripheral nerve injuries. Treatment for these conditions varies depending on the underlying cause but may involve medications, physical therapy, lifestyle changes, or surgery.

Mitochondrial DNA (mtDNA) is the genetic material present in the mitochondria, which are specialized structures within cells that generate energy. Unlike nuclear DNA, which is present in the cell nucleus and inherited from both parents, mtDNA is inherited solely from the mother.

MtDNA is a circular molecule that contains 37 genes, including 13 genes that encode for proteins involved in oxidative phosphorylation, a process that generates energy in the form of ATP. The remaining genes encode for rRNAs and tRNAs, which are necessary for protein synthesis within the mitochondria.

Mutations in mtDNA can lead to a variety of genetic disorders, including mitochondrial diseases, which can affect any organ system in the body. These mutations can also be used in forensic science to identify individuals and establish biological relationships.

Retinal Ganglion Cells (RGCs) are a type of neuron located in the innermost layer of the retina, the light-sensitive tissue at the back of the eye. These cells receive visual information from photoreceptors (rods and cones) via intermediate cells called bipolar cells. RGCs then send this visual information through their long axons to form the optic nerve, which transmits the signals to the brain for processing and interpretation as vision.

There are several types of RGCs, each with distinct morphological and functional characteristics. Some RGCs are specialized in detecting specific features of the visual scene, such as motion, contrast, color, or brightness. The diversity of RGCs allows for a rich and complex representation of the visual world in the brain.

Damage to RGCs can lead to various visual impairments, including loss of vision, reduced visual acuity, and altered visual fields. Conditions associated with RGC damage or degeneration include glaucoma, optic neuritis, ischemic optic neuropathy, and some inherited retinal diseases.

Hereditary Sensory and Motor Neuropathy (HSMN) is a group of inherited disorders that affect the peripheral nerves, which are the nerves outside the brain and spinal cord. These nerves transmit information between the brain and muscles, as well as sensations such as touch, pain, heat, and cold.

HSMN is characterized by progressive degeneration of these peripheral nerves, leading to muscle weakness, numbness, and tingling sensations, particularly in the hands and feet. The condition can also affect the autonomic nervous system, which controls involuntary functions such as heart rate, blood pressure, and digestion.

HSMN is caused by genetic mutations that are inherited from one or both parents. There are several types of HSMN, each with its own specific symptoms, severity, and pattern of inheritance. The most common form is Charcot-Marie-Tooth disease (CMT), which affects both motor and sensory nerves.

Treatment for HSMN typically focuses on managing the symptoms and preventing complications. This may include physical therapy, bracing or orthopedic surgery to support weakened muscles, pain management, and lifestyle modifications such as avoiding activities that aggravate symptoms. There is currently no cure for HSMN, but ongoing research is aimed at developing new treatments and therapies to slow or halt the progression of the disease.

Autosomal dominant optic atrophy (ADOA) is a genetic disorder that affects the optic nerve, which transmits visual information from the eye to the brain. The term "optic atrophy" refers to degeneration or damage to the optic nerve. In ADOA, this condition is inherited in an autosomal dominant manner, meaning that only one copy of the mutated gene, located on one of the autosomal chromosomes (not a sex chromosome), needs to be present for the individual to develop the disorder.

The most common form of ADOA is caused by mutations in the OPA1 gene, which provides instructions for making a protein involved in the maintenance of mitochondria, the energy-producing structures in cells. The exact role of this protein in optic nerve function is not fully understood, but it is thought to play a critical role in maintaining the health and function of retinal ganglion cells, which are the neurons that make up the optic nerve.

In ADOA, mutations in the OPA1 gene lead to progressive degeneration of retinal ganglion cells and their axons (nerve fibers) within the optic nerve. This results in decreased visual acuity, color vision deficits, and a characteristic visual field defect called centrocecal scotoma, which is an area of blindness near the center of the visual field. The onset and severity of these symptoms can vary widely among individuals with ADOA.

It's important to note that medical definitions may contain complex terminology. In simpler terms, autosomal dominant optic atrophy (ADOA) is a genetic condition affecting the optic nerve, leading to decreased visual acuity and other vision problems due to degeneration of retinal ganglion cells. The disorder is inherited in an autosomal dominant manner, meaning only one copy of the mutated gene is needed for the individual to develop ADOA.

The optic chiasm is a structure in the brain where the optic nerves from each eye meet and cross. This allows for the integration of visual information from both eyes into the brain's visual cortex, creating a single, combined image of the visual world. The optic chiasm plays an important role in the processing of visual information and helps to facilitate depth perception and other complex visual tasks. Damage to the optic chiasm can result in various visual field deficits, such as bitemporal hemianopsia, where there is a loss of vision in the outer halves (temporal fields) of both eyes' visual fields.

Visual fields refer to the total area in which objects can be seen while keeping the eyes focused on a central point. It is the entire area that can be observed using peripheral (side) vision while the eye gazes at a fixed point. A visual field test is used to detect blind spots or gaps (scotomas) in a person's vision, which could indicate various medical conditions such as glaucoma, retinal damage, optic nerve disease, brain tumors, or strokes. The test measures both the central and peripheral vision and maps the entire area that can be seen when focusing on a single point.

Visual acuity is a measure of the sharpness or clarity of vision. It is usually tested by reading an eye chart from a specific distance, such as 20 feet (6 meters). The standard eye chart used for this purpose is called the Snellen chart, which contains rows of letters that decrease in size as you read down the chart.

Visual acuity is typically expressed as a fraction, with the numerator representing the testing distance and the denominator indicating the smallest line of type that can be read clearly. For example, if a person can read the line on the eye chart that corresponds to a visual acuity of 20/20, it means they have normal vision at 20 feet. If their visual acuity is 20/40, it means they must be as close as 20 feet to see what someone with normal vision can see at 40 feet.

It's important to note that visual acuity is just one aspect of overall vision and does not necessarily reflect other important factors such as peripheral vision, depth perception, color vision, or contrast sensitivity.

Papilledema is a medical term that refers to swelling of the optic nerve head, also known as the disc, which is the point where the optic nerve enters the back of the eye (the retina). This swelling can be caused by increased pressure within the skull, such as from brain tumors, meningitis, or idiopathic intracranial hypertension. Papilledema is usually detected through a routine eye examination and may be accompanied by symptoms such as headaches, visual disturbances, and nausea. If left untreated, papilledema can lead to permanent vision loss.

NADH dehydrogenase, also known as Complex I, is an enzyme complex in the electron transport chain located in the inner mitochondrial membrane. It catalyzes the oxidation of NADH to NAD+ and the reduction of coenzyme Q to ubiquinol, playing a crucial role in cellular respiration and energy production. The reaction involves the transfer of electrons from NADH to coenzyme Q, which contributes to the generation of a proton gradient across the membrane, ultimately leading to ATP synthesis. Defects in NADH dehydrogenase can result in various mitochondrial diseases and disorders.

Vision disorders refer to a wide range of conditions that affect the visual system and result in various symptoms, such as blurry vision, double vision, distorted vision, impaired depth perception, and difficulty with visual tracking or focusing. These disorders can be categorized into several types, including:

1. Refractive errors: These occur when the shape of the eye prevents light from focusing directly on the retina, resulting in blurry vision. Examples include myopia (nearsightedness), hyperopia (farsightedness), astigmatism, and presbyopia (age-related loss of near vision).
2. Strabismus: Also known as crossed eyes or walleye, strabismus is a misalignment of the eyes where they point in different directions, which can lead to double vision or loss of depth perception.
3. Amblyopia: Often called lazy eye, amblyopia is a condition where one eye has reduced vision due to lack of proper visual development during childhood. It may be caused by strabismus, refractive errors, or other factors that interfere with normal visual development.
4. Accommodative disorders: These involve problems with the focusing ability of the eyes, such as convergence insufficiency (difficulty focusing on close objects) and accommodative dysfunction (inability to maintain clear vision at different distances).
5. Binocular vision disorders: These affect how the eyes work together as a team, leading to issues like poor depth perception, eye strain, and headaches. Examples include convergence insufficiency, divergence excess, and suppression.
6. Ocular motility disorders: These involve problems with eye movement, such as nystagmus (involuntary eye movements), strabismus, or restricted extraocular muscle function.
7. Visual processing disorders: These affect the brain's ability to interpret and make sense of visual information, even when the eyes themselves are healthy. Symptoms may include difficulty with reading, recognizing shapes and objects, and understanding spatial relationships.
8. Low vision: This term refers to significant visual impairment that cannot be fully corrected with glasses, contact lenses, medication, or surgery. It includes conditions like macular degeneration, diabetic retinopathy, glaucoma, and cataracts.
9. Blindness: Complete loss of sight in both eyes, which can be caused by various factors such as injury, disease, or genetic conditions.

Graves' ophthalmopathy, also known as Graves' eye disease or thyroid eye disease, is an autoimmune condition that affects the eyes. It often occurs in individuals with Graves' disease, an autoimmune disorder that causes hyperthyroidism (overactive thyroid gland). However, it can also occur in people without Graves' disease.

In Graves' ophthalmopathy, the immune system attacks the tissue behind the eyes, causing inflammation and enlargement of the muscles, fatty tissue, and connective tissue within the orbit (eye socket). This leads to symptoms such as:

1. Protrusion or bulging of the eyes (exophthalmos)
2. Redness and swelling of the eyelids
3. Double vision (diplopia) due to restricted eye movement
4. Pain and discomfort, especially when looking up, down, or sideways
5. Light sensitivity (photophobia)
6. Tearing and dryness in the eyes
7. Vision loss in severe cases

The treatment for Graves' ophthalmopathy depends on the severity of the symptoms and may include medications to manage inflammation, eye drops or ointments for dryness, prisms to correct double vision, or surgery for severe cases.

Glaucoma is a group of eye conditions that damage the optic nerve, often caused by an abnormally high pressure in the eye (intraocular pressure). This damage can lead to permanent vision loss or even blindness if left untreated. The most common type is open-angle glaucoma, which has no warning signs and progresses slowly. Angle-closure glaucoma, on the other hand, can cause sudden eye pain, redness, nausea, and vomiting, as well as rapid vision loss. Other less common types of glaucoma also exist. While there is no cure for glaucoma, early detection and treatment can help slow or prevent further vision loss.

Intraocular pressure (IOP) is the fluid pressure within the eye, specifically within the anterior chamber, which is the space between the cornea and the iris. It is measured in millimeters of mercury (mmHg). The aqueous humor, a clear fluid that fills the anterior chamber, is constantly produced and drained, maintaining a balance that determines the IOP. Normal IOP ranges from 10-21 mmHg, with average values around 15-16 mmHg. Elevated IOP is a key risk factor for glaucoma, a group of eye conditions that can lead to optic nerve damage and vision loss if not treated promptly and effectively. Regular monitoring of IOP is essential in diagnosing and managing glaucoma and other ocular health issues.

In medical terms, the orbit refers to the bony cavity or socket in the skull that contains and protects the eye (eyeball) and its associated structures, including muscles, nerves, blood vessels, fat, and the lacrimal gland. The orbit is made up of several bones: the frontal bone, sphenoid bone, zygomatic bone, maxilla bone, and palatine bone. These bones form a pyramid-like shape that provides protection for the eye while also allowing for a range of movements.

Blindness is a condition of complete or near-complete vision loss. It can be caused by various factors such as eye diseases, injuries, or birth defects. Total blindness means that a person cannot see anything at all, while near-complete blindness refers to having only light perception or the ability to perceive the direction of light, but not able to discern shapes or forms. Legal blindness is a term used to define a certain level of visual impairment that qualifies an individual for government assistance and benefits; it usually means best corrected visual acuity of 20/200 or worse in the better eye, or a visual field no greater than 20 degrees in diameter.

Nerve fibers are specialized structures that constitute the long, slender processes (axons) of neurons (nerve cells). They are responsible for conducting electrical impulses, known as action potentials, away from the cell body and transmitting them to other neurons or effector organs such as muscles and glands. Nerve fibers are often surrounded by supportive cells called glial cells and are grouped together to form nerve bundles or nerves. These fibers can be myelinated (covered with a fatty insulating sheath called myelin) or unmyelinated, which influences the speed of impulse transmission.

A visual field test is a method used to measure an individual's entire scope of vision, which includes what can be seen straight ahead and in peripheral (or side) vision. During the test, the person being tested is asked to focus on a central point while gradually identifying the appearance of objects moving into their peripheral vision. The visual field test helps detect blind spots (scotomas) or gaps in the visual field, which can be caused by various conditions such as glaucoma, brain injury, optic nerve damage, or retinal disorders. It's an essential tool for diagnosing and monitoring eye-related diseases and conditions.

Penetrance, in medical genetics, refers to the proportion of individuals with a particular genetic variant or mutation who exhibit clinical features or symptoms of a resulting disease. It is often expressed as a percentage, with complete penetrance indicating that all individuals with the genetic change will develop the disease, and reduced or incomplete penetrance suggesting that not all individuals with the genetic change will necessarily develop the disease, even if they express some of its characteristics.

Penetrance can vary depending on various factors such as age, sex, environmental influences, and interactions with other genes. Incomplete penetrance is common in many genetic disorders, making it challenging to predict who will develop symptoms based solely on their genotype.

Hereditary Sensory and Autonomic Neuropathies (HSANs) are a group of inherited disorders that affect the sensory and autonomic nerves. These nerves are responsible for transmitting information about senses such as touch, pain, temperature, and vibration to the brain, as well as controlling automatic functions like blood pressure, heart rate, and digestion.

HSANs are caused by genetic mutations that result in damage to the peripheral nerves. There are several types of HSANs, each with its own specific symptoms and patterns of inheritance. Some common features include:

* Loss of sensation in the hands and feet
* Pain insensitivity
* Absent or reduced reflexes
* Autonomic dysfunction, such as abnormal sweating, blood pressure regulation, and digestive problems

The severity and progression of HSANs can vary widely depending on the specific type and individual factors. Treatment is generally focused on managing symptoms and preventing complications, such as injuries from lack of pain sensation or falls due to balance problems. Early diagnosis and intervention are important for optimizing outcomes.

A pupil disorder refers to any abnormality or condition affecting the size, shape, or reactivity of the pupils, the circular black openings in the center of the eyes through which light enters. The pupil's primary function is to regulate the amount of light that reaches the retina, adjusting its size accordingly.

There are several types of pupil disorders, including:

1. Anisocoria: A condition characterized by unequal pupil sizes in either one or both eyes. This may be caused by various factors, such as nerve damage, trauma, inflammation, or medication side effects.

2. Horner's syndrome: A neurological disorder affecting the autonomic nervous system, resulting in a smaller pupil (miosis), partial eyelid droop (ptosis), and decreased sweating (anhidrosis) on the same side of the face. It is caused by damage to the sympathetic nerve pathway.

3. Adie's tonic pupil: A condition characterized by a dilated, poorly reactive pupil due to damage to the ciliary ganglion or short ciliary nerves. This disorder usually affects one eye and may be associated with decreased deep tendon reflexes in the affected limbs.

4. Argyll Robertson pupil: A condition where the pupils are small, irregularly shaped, and do not react to light but constrict when focusing on nearby objects (accommodation). This disorder is often associated with neurosyphilis or other brainstem disorders.

5. Pupillary dilation: Abnormally dilated pupils can be a sign of various conditions, such as drug use (e.g., atropine, cocaine), brainstem injury, Adie's tonic pupil, or oculomotor nerve palsy.

6. Pupillary constriction: Abnormally constricted pupils can be a sign of various conditions, such as Horner's syndrome, Argyll Robertson pupil, drug use (e.g., opioids, pilocarpine), or oculomotor nerve palsy.

7. Light-near dissociation: A condition where the pupils do not react to light but constrict when focusing on nearby objects. This can be seen in Argyll Robertson pupil and Adie's tonic pupil.

Prompt evaluation by an ophthalmologist or neurologist is necessary for accurate diagnosis and management of these conditions.

Open-angle glaucoma is a chronic, progressive type of glaucoma characterized by the gradual loss of optic nerve fibers and resulting in visual field defects. It is called "open-angle" because the angle where the iris meets the cornea (trabecular meshwork) appears to be normal and open on examination. The exact cause of this condition is not fully understood, but it is associated with increased resistance to the outflow of aqueous humor within the trabecular meshwork, leading to an increase in intraocular pressure (IOP). This elevated IOP can cause damage to the optic nerve and result in vision loss.

The onset of open-angle glaucoma is often asymptomatic, making regular comprehensive eye examinations crucial for early detection and management. Treatment typically involves lowering IOP using medications, laser therapy, or surgery to prevent further optic nerve damage and preserve vision.

Evoked potentials, visual, also known as visually evoked potentials (VEPs), are electrical responses recorded from the brain following the presentation of a visual stimulus. These responses are typically measured using electroencephalography (EEG) and can provide information about the functioning of the visual pathways in the brain.

There are several types of VEPs, including pattern-reversal VEPs and flash VEPs. Pattern-reversal VEPs are elicited by presenting alternating checkerboard patterns, while flash VEPs are elicited by flashing a light. The responses are typically analyzed in terms of their latency (the time it takes for the response to occur) and amplitude (the size of the response).

VEPs are often used in clinical settings to help diagnose and monitor conditions that affect the visual system, such as multiple sclerosis, optic neuritis, and brainstem tumors. They can also be used in research to study the neural mechanisms underlying visual perception.

I must clarify that the term "pedigree" is not typically used in medical definitions. Instead, it is often employed in genetics and breeding, where it refers to the recorded ancestry of an individual or a family, tracing the inheritance of specific traits or diseases. In human genetics, a pedigree can help illustrate the pattern of genetic inheritance in families over multiple generations. However, it is not a medical term with a specific clinical definition.

Polyneuropathy is a medical condition that refers to the damage or dysfunction of peripheral nerves (nerves outside the brain and spinal cord) in multiple areas of the body. These nerves are responsible for transmitting sensory, motor, and autonomic signals between the central nervous system and the rest of the body.

In polyneuropathies, this communication is disrupted, leading to various symptoms depending on the type and extent of nerve damage. Commonly reported symptoms include:

1. Numbness or tingling in the hands and feet
2. Muscle weakness and cramps
3. Loss of reflexes
4. Burning or stabbing pain
5. Balance and coordination issues
6. Increased sensitivity to touch
7. Autonomic dysfunction, such as bowel, bladder, or digestive problems, and changes in blood pressure

Polyneuropathies can be caused by various factors, including diabetes, alcohol abuse, nutritional deficiencies, autoimmune disorders, infections, toxins, inherited genetic conditions, or idiopathic (unknown) causes. The treatment for polyneuropathy depends on the underlying cause and may involve managing underlying medical conditions, physical therapy, pain management, and lifestyle modifications.

The sural nerve is a purely sensory peripheral nerve in the lower leg and foot. It provides sensation to the outer ( lateral) aspect of the little toe and the adjacent side of the fourth toe, as well as a small portion of the skin on the back of the leg between the ankle and knee joints.

The sural nerve is formed by the union of branches from the tibial and common fibular nerves (branches of the sciatic nerve) in the lower leg. It runs down the calf, behind the lateral malleolus (the bony prominence on the outside of the ankle), and into the foot.

The sural nerve is often used as a donor nerve during nerve grafting procedures due to its consistent anatomy and relatively low risk for morbidity at the donor site.

Optic disk drusen are small, calcified deposits that form within the optic nerve head, also known as the optic disc. They are made up of protein and calcium salts and can vary in size and number. These deposits can be seen on ophthalmic examination using an instrument called an ophthalmoscope.

Optic disk drusen are typically asymptomatic and are often discovered during routine eye examinations. However, in some cases, they may cause visual disturbances or even vision loss if they compress the optic nerve fibers. They can also increase the risk of developing other eye conditions such as glaucoma.

Optic disk drusen are more commonly found in individuals with a family history of the condition and tend to occur in younger people, typically before the age of 40. While there is no cure for optic disk drusen, regular eye examinations can help monitor any changes in the condition and manage any associated visual symptoms or complications.

Mitochondrial diseases are a group of disorders caused by dysfunctions in the mitochondria, which are the energy-producing structures in cells. These diseases can affect people of any age and can manifest in various ways, depending on which organs or systems are affected. Common symptoms include muscle weakness, neurological problems, cardiac disease, diabetes, and vision/hearing loss. Mitochondrial diseases can be inherited from either the mother's or father's side, or they can occur spontaneously due to genetic mutations. They can range from mild to severe and can even be life-threatening in some cases.

An axon is a long, slender extension of a neuron (a type of nerve cell) that conducts electrical impulses (nerve impulses) away from the cell body to target cells, such as other neurons or muscle cells. Axons can vary in length from a few micrometers to over a meter long and are typically surrounded by a myelin sheath, which helps to insulate and protect the axon and allows for faster transmission of nerve impulses.

Axons play a critical role in the functioning of the nervous system, as they provide the means by which neurons communicate with one another and with other cells in the body. Damage to axons can result in serious neurological problems, such as those seen in spinal cord injuries or neurodegenerative diseases like multiple sclerosis.

Nerve compression syndromes refer to a group of conditions characterized by the pressure or irritation of a peripheral nerve, causing various symptoms such as pain, numbness, tingling, and weakness in the affected area. This compression can occur due to several reasons, including injury, repetitive motion, bone spurs, tumors, or swelling. Common examples of nerve compression syndromes include carpal tunnel syndrome, cubital tunnel syndrome, radial nerve compression, and ulnar nerve entrapment at the wrist or elbow. Treatment options may include physical therapy, splinting, medications, injections, or surgery, depending on the severity and underlying cause of the condition.

Neural conduction is the process by which electrical signals, known as action potentials, are transmitted along the axon of a neuron (nerve cell) to transmit information between different parts of the nervous system. This electrical impulse is generated by the movement of ions across the neuronal membrane, and it propagates down the length of the axon until it reaches the synapse, where it can then stimulate the release of neurotransmitters to communicate with other neurons or target cells. The speed of neural conduction can vary depending on factors such as the diameter of the axon, the presence of myelin sheaths (which act as insulation and allow for faster conduction), and the temperature of the environment.

The retina is the innermost, light-sensitive layer of tissue in the eye of many vertebrates and some cephalopods. It receives light that has been focused by the cornea and lens, converts it into neural signals, and sends these to the brain via the optic nerve. The retina contains several types of photoreceptor cells including rods (which handle vision in low light) and cones (which are active in bright light and are capable of color vision).

In medical terms, any pathological changes or diseases affecting the retinal structure and function can lead to visual impairment or blindness. Examples include age-related macular degeneration, diabetic retinopathy, retinal detachment, and retinitis pigmentosa among others.

Fluorescein angiography is a medical diagnostic procedure used in ophthalmology to examine the blood flow in the retina and choroid, which are the inner layers of the eye. This test involves injecting a fluorescent dye, Fluorescein, into a patient's arm vein. As the dye reaches the blood vessels in the eye, a specialized camera takes rapid sequences of photographs to capture the dye's circulation through the retina and choroid.

The images produced by fluorescein angiography can help doctors identify any damage to the blood vessels, leakage, or abnormal growth of new blood vessels. This information is crucial in diagnosing and managing various eye conditions such as age-related macular degeneration, diabetic retinopathy, retinal vein occlusions, and inflammatory eye diseases.

It's important to note that while fluorescein angiography is a valuable diagnostic tool, it does carry some risks, including temporary side effects like nausea, vomiting, or allergic reactions to the dye. In rare cases, severe adverse reactions can occur, so patients should discuss these potential risks with their healthcare provider before undergoing the procedure.

The optic lobe in non-mammals refers to a specific region of the brain that is responsible for processing visual information. It is a part of the protocerebrum in the insect brain and is analogous to the mammalian visual cortex. The optic lobes receive input directly from the eyes via the optic nerves and are involved in the interpretation and integration of visual stimuli, enabling non-mammals to perceive and respond to their environment. In some invertebrates, like insects, the optic lobe is further divided into subregions, including the lamina, medulla, and lobula, each with distinct functions in visual processing.

"Fundus Oculi" is a medical term that refers to the back part of the interior of the eye, including the optic disc, macula, fovea, retinal vasculature, and peripheral retina. It is the area where light is focused and then transmitted to the brain via the optic nerve, forming visual images. Examinations of the fundus oculi are crucial for detecting various eye conditions such as diabetic retinopathy, macular degeneration, glaucoma, and other retinal diseases. The examination is typically performed using an ophthalmoscope or a specialized camera called a retinal camera.

Optic flow is not a medical term per se, but rather a term used in the field of visual perception and neuroscience. It refers to the pattern of motion of objects in the visual field that occurs as an observer moves through the environment. This pattern of motion is important for the perception of self-motion and the estimation of egocentric distance (the distance of objects in the environment relative to the observer). Optic flow has been studied in relation to various clinical populations, such as individuals with vestibular disorders or visual impairments, who may have difficulty processing optic flow information.

Giant Cell Arteritis (GCA), also known as Temporal Arteritis, is a chronic inflammatory disease affecting large and medium-sized arteries, most commonly the temporal artery. It primarily occurs in people over 50 years old. The condition is characterized by the infiltration of the artery walls with immune cells, leading to inflammation, swelling, and damage. This can restrict blood flow, causing various symptoms.

The key feature of GCA is the presence of multinucleated giant cells, which are large collections of fused immune cells, in the affected artery walls. These cells are a hallmark of this condition when viewed under a microscope.

Common symptoms include new onset of severe headaches, scalp tenderness, jaw pain while chewing (called jaw claudication), vision problems, and systemic symptoms such as fever, fatigue, and weight loss. If left untreated, GCA can lead to serious complications like blindness or stroke. Treatment typically involves high-dose corticosteroids to reduce inflammation and prevent further damage.

Optical coherence tomography (OCT) is a non-invasive imaging technique that uses low-coherence light to capture high-resolution cross-sectional images of biological tissues, particularly the retina and other ocular structures. OCT works by measuring the echo time delay of light scattered back from different depths within the tissue, creating a detailed map of the tissue's structure. This technique is widely used in ophthalmology to diagnose and monitor various eye conditions such as macular degeneration, diabetic retinopathy, and glaucoma.

Ulnar neuropathies refer to conditions that cause damage or dysfunction to the ulnar nerve, which is one of the major nerves in the arm. The ulnar nerve runs down the forearm and through the wrist to the hand, where it provides sensation to the pinky finger and half of the ring finger, as well as motor function to the muscles that control finger movements.

Ulnar neuropathies can result from various causes, including trauma, compression, entrapment, or inflammation. Common symptoms include numbness, tingling, or weakness in the hand and fingers, particularly in the pinky and ring fingers. In more severe cases, muscle wasting and loss of dexterity may occur.

There are several types of ulnar neuropathies, depending on the location and cause of the nerve damage. For example, cubital tunnel syndrome is a type of ulnar neuropathy that results from compression of the ulnar nerve at the elbow, while ulnar nerve entrapment at the wrist (also known as Guyon's canal syndrome) can also cause ulnar neuropathies. Treatment options for ulnar neuropathies may include physical therapy, medication, or surgery, depending on the severity and underlying cause of the condition.

I'm sorry for any confusion, but "photography" is not a term typically used in medical definitions. Photography refers to the art, application, or process of creating images by recording light or other electromagnetic radiation, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film.

If you're looking for a medical term related to imaging, there are several terms that might be relevant, such as:

1. Radiography: This is a technique using X-rays to visualize the internal structures of the body.
2. Ultrasonography: Also known as ultrasound, this is a diagnostic imaging technique using high-frequency sound waves to create images of the inside of the body.
3. Computed Tomography (CT): A type of imaging that uses X-rays to create detailed cross-sectional images of the body.
4. Magnetic Resonance Imaging (MRI): A type of imaging that uses magnetic fields and radio waves to create detailed images of the organs and tissues within the body.
5. Nuclear Medicine: This is a branch of medical imaging that uses small amounts of radioactive material to diagnose and treat diseases.

If you have any questions related to medical definitions or topics, feel free to ask!

Charcot-Marie-Tooth disease (CMT) is a group of inherited disorders that cause nerve damage, primarily affecting the peripheral nerves. These are the nerves that transmit signals between the brain and spinal cord to the rest of the body. CMT affects both motor and sensory nerves, leading to muscle weakness and atrophy, as well as numbness or tingling in the hands and feet.

The disease is named after the three physicians who first described it: Jean-Martin Charcot, Pierre Marie, and Howard Henry Tooth. CMT is characterized by its progressive nature, meaning symptoms typically worsen over time, although the rate of progression can vary significantly among individuals.

There are several types of CMT, classified based on their genetic causes and patterns of inheritance. The two most common forms are CMT1 and CMT2:

1. CMT1: This form is caused by mutations in the genes responsible for the myelin sheath, which insulates peripheral nerves and allows for efficient signal transmission. As a result, demyelination occurs, slowing down nerve impulses and causing muscle weakness, particularly in the lower limbs. Symptoms usually begin in childhood or adolescence and include foot drop, high arches, and hammertoes.
2. CMT2: This form is caused by mutations in the genes responsible for the axons, the nerve fibers that transmit signals within peripheral nerves. As a result, axonal degeneration occurs, leading to muscle weakness and atrophy. Symptoms usually begin in early adulthood and progress more slowly than CMT1. They primarily affect the lower limbs but can also involve the hands and arms.

Diagnosis of CMT typically involves a combination of clinical evaluation, family history, nerve conduction studies, and genetic testing. While there is no cure for CMT, treatment focuses on managing symptoms and maintaining mobility and function through physical therapy, bracing, orthopedic surgery, and pain management.

Retinal artery occlusion (RAO) is a medical condition characterized by the blockage or obstruction of the retinal artery, which supplies oxygenated blood to the retina. This blockage typically occurs due to embolism (a small clot or debris that travels to the retinal artery), thrombosis (blood clot formation in the artery), or vasculitis (inflammation of the blood vessels).

There are two types of retinal artery occlusions:

1. Central Retinal Artery Occlusion (CRAO): This type occurs when the main retinal artery is obstructed, affecting the entire inner layer of the retina. It can lead to severe and sudden vision loss in the affected eye.
2. Branch Retinal Artery Occlusion (BRAO): This type affects a branch of the retinal artery, causing visual field loss in the corresponding area. Although it is less severe than CRAO, it can still result in noticeable vision impairment.

Immediate medical attention is crucial for both types of RAO to improve the chances of recovery and minimize potential damage to the eye and vision. Treatment options may include medications, laser therapy, or surgery, depending on the underlying cause and the severity of the condition.

Diagnostic techniques in ophthalmology refer to the various methods and tests used by eye specialists (ophthalmologists) to examine, evaluate, and diagnose conditions related to the eyes and visual system. Here are some commonly used diagnostic techniques:

1. Visual Acuity Testing: This is a basic test to measure the sharpness of a person's vision. It typically involves reading letters or numbers from an eye chart at a specific distance.
2. Refraction Test: This test helps determine the correct lens prescription for glasses or contact lenses by measuring how light is bent as it passes through the cornea and lens.
3. Slit Lamp Examination: A slit lamp is a microscope that allows an ophthalmologist to examine the structures of the eye, including the cornea, iris, lens, and retina, in great detail.
4. Tonometry: This test measures the pressure inside the eye (intraocular pressure) to detect conditions like glaucoma. Common methods include applanation tonometry and non-contact tonometry.
5. Retinal Imaging: Several techniques are used to capture images of the retina, including fundus photography, fluorescein angiography, and optical coherence tomography (OCT). These tests help diagnose conditions like macular degeneration, diabetic retinopathy, and retinal detachments.
6. Color Vision Testing: This test evaluates a person's ability to distinguish between different colors, which can help detect color vision deficiencies or neurological disorders affecting the visual pathway.
7. Visual Field Testing: This test measures a person's peripheral (or side) vision and can help diagnose conditions like glaucoma, optic nerve damage, or brain injuries.
8. Pupillary Reactions Tests: These tests evaluate how the pupils respond to light and near objects, which can provide information about the condition of the eye's internal structures and the nervous system.
9. Ocular Motility Testing: This test assesses eye movements and alignment, helping diagnose conditions like strabismus (crossed eyes) or nystagmus (involuntary eye movement).
10. Corneal Topography: This non-invasive imaging technique maps the curvature of the cornea, which can help detect irregularities, assess the fit of contact lenses, and plan refractive surgery procedures.

Surgical decompression is a medical procedure that involves relieving pressure on a nerve or tissue by creating additional space. This is typically accomplished through the removal of a portion of bone or other tissue that is causing the compression. The goal of surgical decompression is to alleviate symptoms such as pain, numbness, tingling, or weakness caused by the compression.

In the context of spinal disorders, surgical decompression is often used to treat conditions such as herniated discs, spinal stenosis, or bone spurs that are compressing nerves in the spine. The specific procedure used may vary depending on the location and severity of the compression, but common techniques include laminectomy, discectomy, and foraminotomy.

It's important to note that surgical decompression is a significant medical intervention that carries risks such as infection, bleeding, and injury to surrounding tissues. As with any surgery, it should be considered as a last resort after other conservative treatments have been tried and found to be ineffective. A thorough evaluation by a qualified medical professional is necessary to determine whether surgical decompression is appropriate in a given case.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

I'm sorry for any confusion, but "Optics and Photonics" is a broad field that encompasses various scientific and engineering disciplines. It doesn't have a specific medical definition, as it's not a term typically used in a medical context.

However, I can provide a general definition:

Optics is the study of light and its interactions with matter. This includes how light is produced, controlled, transmitted, and detected. It involves phenomena such as reflection, refraction, diffraction, and interference.

Photonics, on the other hand, is a branch of optics that deals with the generation, detection, and manipulation of individual photons, the basic units of light. Photonics is often applied to technologies such as lasers, fiber optics, and optical communications.

In a medical context, these fields might be used in various diagnostic and therapeutic applications, such as endoscopes, ophthalmic devices, laser surgery, and imaging technologies like MRI and CT scans. But the terms "Optics" and "Photonics" themselves are not medical conditions or treatments.

The Autonomic Nervous System (ANS) is a part of the nervous system that controls involuntary actions, such as heart rate, digestion, respiratory rate, pupillary response, urination, and sexual arousal. It consists of two subdivisions: the sympathetic and parasympathetic nervous systems, which generally have opposing effects and maintain homeostasis in the body.

Autonomic Nervous System Diseases (also known as Autonomic Disorders or Autonomic Neuropathies) refer to a group of conditions that affect the functioning of the autonomic nervous system. These diseases can cause damage to the nerves that control automatic functions, leading to various symptoms and complications.

Autonomic Nervous System Diseases can be classified into two main categories:

1. Primary Autonomic Nervous System Disorders: These are conditions that primarily affect the autonomic nervous system without any underlying cause. Examples include:
* Pure Autonomic Failure (PAF): A rare disorder characterized by progressive loss of autonomic nerve function, leading to symptoms such as orthostatic hypotension, urinary retention, and constipation.
* Multiple System Atrophy (MSA): A degenerative neurological disorder that affects both the autonomic nervous system and movement coordination. Symptoms may include orthostatic hypotension, urinary incontinence, sexual dysfunction, and Parkinsonian features like stiffness and slowness of movements.
* Autonomic Neuropathy associated with Parkinson's Disease: Some individuals with Parkinson's disease develop autonomic symptoms such as orthostatic hypotension, constipation, and urinary dysfunction due to the degeneration of autonomic nerves.
2. Secondary Autonomic Nervous System Disorders: These are conditions that affect the autonomic nervous system as a result of an underlying cause or disease. Examples include:
* Diabetic Autonomic Neuropathy: A complication of diabetes mellitus that affects the autonomic nerves, leading to symptoms such as orthostatic hypotension, gastroparesis (delayed gastric emptying), and sexual dysfunction.
* Autoimmune-mediated Autonomic Neuropathies: Conditions like Guillain-Barré syndrome or autoimmune autonomic ganglionopathy can cause autonomic symptoms due to the immune system attacking the autonomic nerves.
* Infectious Autonomic Neuropathies: Certain infections, such as HIV or Lyme disease, can lead to autonomic dysfunction as a result of nerve damage.
* Toxin-induced Autonomic Neuropathy: Exposure to certain toxins, like heavy metals or organophosphate pesticides, can cause autonomic neuropathy.

Autonomic nervous system disorders can significantly impact a person's quality of life and daily functioning. Proper diagnosis and management are crucial for improving symptoms and preventing complications. Treatment options may include lifestyle modifications, medications, and in some cases, devices or surgical interventions.

An Optic Nerve Glioma is a type of brain tumor that arises from the glial cells (supportive tissue) within the optic nerve. It is most commonly seen in children, particularly those with neurofibromatosis type 1 (NF1). These tumors are typically slow-growing and may not cause any symptoms, especially if they are small. However, as they grow larger, they can put pressure on the optic nerve, leading to vision loss or other visual disturbances. In some cases, these tumors can also affect nearby structures in the brain, causing additional neurological symptoms. Treatment options may include observation, chemotherapy, radiation therapy, or surgery, depending on the size and location of the tumor, as well as the patient's age and overall health.

Arteritis is a medical condition characterized by inflammation of the arteries. It is also known as vasculitis of the arteries. The inflammation can cause the walls of the arteries to thicken and narrow, reducing blood flow to affected organs or tissues. There are several types of arteritis, including:

1. Giant cell arteritis (GCA): Also known as temporal arteritis, it is a condition that mainly affects the large and medium-sized arteries in the head and neck. The inflammation can cause headaches, jaw pain, scalp tenderness, and vision problems.
2. Takayasu's arteritis: This type of arteritis affects the aorta and its major branches, mainly affecting young women. Symptoms include fever, weight loss, fatigue, and decreased pulse in the arms or legs.
3. Polyarteritis nodosa (PAN): PAN is a rare systemic vasculitis that can affect medium-sized arteries throughout the body. It can cause a wide range of symptoms, including fever, rash, abdominal pain, and muscle weakness.
4. Kawasaki disease: This is a type of arteritis that mainly affects children under the age of 5. It causes inflammation in the blood vessels throughout the body, leading to fever, rash, swollen lymph nodes, and red eyes.

The exact cause of arteritis is not fully understood, but it is believed to be an autoimmune disorder, where the body's immune system mistakenly attacks its own tissues. Treatment for arteritis typically involves medications to reduce inflammation and suppress the immune system.

Alcoholic neuropathy is a type of nerve damage that occurs due to excessive alcohol consumption. It's caused by the toxic effects of alcohol and its byproducts on nerves throughout the body, particularly in the peripheral nervous system. The condition typically develops over time, with symptoms becoming more severe as alcohol abuse continues.

The symptoms of alcoholic neuropathy can vary widely depending on which nerves are affected. However, common symptoms include:

1. Numbness or tingling in the arms and legs
2. Muscle weakness and cramps
3. Loss of reflexes
4. Difficulty with balance and coordination
5. Pain or burning sensations in the extremities
6. Heat intolerance
7. Bladder and bowel dysfunction
8. Sexual dysfunction

Treatment for alcoholic neuropathy typically involves addressing the underlying alcohol abuse, as well as managing symptoms with medications and physical therapy. In severe cases, hospitalization may be necessary to monitor and manage complications. It's important to note that abstaining from alcohol is the only way to prevent further nerve damage and improve symptoms over time.

Ophthalmoscopy is a medical examination technique used by healthcare professionals to observe the interior structures of the eye, including the retina, optic disc, and vitreous humor. This procedure typically involves using an ophthalmoscope, a handheld device that consists of a light and magnifying lenses. The healthcare provider looks through the ophthalmoscope and directly observes the internal structures of the eye by illuminating them.

There are several types of ophthalmoscopy, including direct ophthalmoscopy, indirect ophthalmoscopy, and slit-lamp biomicroscopy. Each type has its own advantages and disadvantages, and they may be used in different situations depending on the specific clinical situation and the information needed.

Ophthalmoscopy is an important diagnostic tool for detecting and monitoring a wide range of eye conditions, including diabetic retinopathy, glaucoma, age-related macular degeneration, and other retinal disorders. It can also provide valuable information about the overall health of the individual, as changes in the appearance of the retina or optic nerve may indicate the presence of systemic diseases such as hypertension or diabetes.

Retinal diseases refer to a group of conditions that affect the retina, which is the light-sensitive tissue located at the back of the eye. The retina is responsible for converting light into electrical signals that are sent to the brain and interpreted as visual images. Retinal diseases can cause vision loss or even blindness, depending on their severity and location in the retina.

Some common retinal diseases include:

1. Age-related macular degeneration (AMD): A progressive disease that affects the central part of the retina called the macula, causing blurred or distorted vision.
2. Diabetic retinopathy: A complication of diabetes that can damage the blood vessels in the retina, leading to vision loss.
3. Retinal detachment: A serious condition where the retina becomes separated from its underlying tissue, requiring immediate medical attention.
4. Macular edema: Swelling or thickening of the macula due to fluid accumulation, which can cause blurred vision.
5. Retinitis pigmentosa: A group of inherited eye disorders that affect the retina's ability to respond to light, causing progressive vision loss.
6. Macular hole: A small break in the macula that can cause distorted or blurry vision.
7. Retinal vein occlusion: Blockage of the retinal veins that can lead to bleeding, swelling, and potential vision loss.

Treatment for retinal diseases varies depending on the specific condition and its severity. Some treatments include medication, laser therapy, surgery, or a combination of these options. Regular eye exams are essential for early detection and treatment of retinal diseases.

Ciliary arteries are a type of ocular (eye) artery that originate from the posterior ciliary and muscular arteries. They supply blood to the ciliary body, choroid, and iris of the eye. The ciliary body is a part of the eye that contains muscles responsible for accommodation (the ability to focus on objects at different distances). The choroid is a layer of blood vessels that provides oxygen and nutrients to the outer layers of the retina. The iris is the colored part of the eye that controls the amount of light reaching the retina by adjusting the size of the pupil.

The ethmoid sinuses are a pair of air-filled spaces located in the ethmoid bone, which is a part of the skull that forms the upper portion of the nasal cavity and the inner eye socket. These sinuses are divided into anterior and posterior groups and are present in adults, but not at birth. They continue to grow and develop until early adulthood.

The ethmoid sinuses are lined with mucous membrane, which helps to warm, humidify, and filter the air we breathe. They are surrounded by a network of blood vessels and nerves, making them susceptible to inflammation and infection. Inflammation of the ethmoid sinuses can lead to conditions such as sinusitis, which can cause symptoms such as nasal congestion, headache, and facial pain.

Ocular hypertension is a medical condition characterized by elevated pressure within the eye (intraocular pressure or IOP), which is higher than normal but not necessarily high enough to cause any visible damage to the optic nerve or visual field loss. It serves as a significant risk factor for developing glaucoma, a sight-threatening disease.

The normal range of intraocular pressure is typically between 10-21 mmHg (millimeters of mercury). Ocular hypertension is often defined as an IOP consistently above 21 mmHg, although some studies suggest that even pressures between 22-30 mmHg may not cause damage in all individuals. Regular monitoring and follow-up with an ophthalmologist are essential for people diagnosed with ocular hypertension to ensure early detection and management of any potential glaucomatous changes. Treatment options include medications, laser therapy, or surgery to lower the IOP and reduce the risk of glaucoma onset.

DNA Mutational Analysis is a laboratory test used to identify genetic variations or changes (mutations) in the DNA sequence of a gene. This type of analysis can be used to diagnose genetic disorders, predict the risk of developing certain diseases, determine the most effective treatment for cancer, or assess the likelihood of passing on an inherited condition to offspring.

The test involves extracting DNA from a patient's sample (such as blood, saliva, or tissue), amplifying specific regions of interest using polymerase chain reaction (PCR), and then sequencing those regions to determine the precise order of nucleotide bases in the DNA molecule. The resulting sequence is then compared to reference sequences to identify any variations or mutations that may be present.

DNA Mutational Analysis can detect a wide range of genetic changes, including single-nucleotide polymorphisms (SNPs), insertions, deletions, duplications, and rearrangements. The test is often used in conjunction with other diagnostic tests and clinical evaluations to provide a comprehensive assessment of a patient's genetic profile.

It is important to note that not all mutations are pathogenic or associated with disease, and the interpretation of DNA Mutational Analysis results requires careful consideration of the patient's medical history, family history, and other relevant factors.

Electron Transport Complex I, also known as NADH:ubiquinone oxidoreductase, is a large protein complex located in the inner mitochondrial membrane of eukaryotic cells and the cytoplasmic membrane of prokaryotic cells. It is the first complex in the electron transport chain, a series of protein complexes that transfer electrons from NADH to oxygen, driving the synthesis of ATP through chemiosmosis.

Complex I consists of multiple subunits, including a flavin mononucleotide (FMN) cofactor and several iron-sulfur clusters, which facilitate the oxidation of NADH and the reduction of ubiquinone (coenzyme Q). The energy released during this electron transfer process is used to pump protons across the membrane, creating a proton gradient that drives ATP synthesis.

Defects in Complex I can lead to various mitochondrial diseases, including neurological disorders and muscle weakness.

The eye is the organ of sight, primarily responsible for detecting and focusing on visual stimuli. It is a complex structure composed of various parts that work together to enable vision. Here are some of the main components of the eye:

1. Cornea: The clear front part of the eye that refracts light entering the eye and protects the eye from harmful particles and microorganisms.
2. Iris: The colored part of the eye that controls the amount of light reaching the retina by adjusting the size of the pupil.
3. Pupil: The opening in the center of the iris that allows light to enter the eye.
4. Lens: A biconvex structure located behind the iris that further refracts light and focuses it onto the retina.
5. Retina: A layer of light-sensitive cells (rods and cones) at the back of the eye that convert light into electrical signals, which are then transmitted to the brain via the optic nerve.
6. Optic Nerve: The nerve that carries visual information from the retina to the brain.
7. Vitreous: A clear, gel-like substance that fills the space between the lens and the retina, providing structural support to the eye.
8. Conjunctiva: A thin, transparent membrane that covers the front of the eye and the inner surface of the eyelids.
9. Extraocular Muscles: Six muscles that control the movement of the eye, allowing for proper alignment and focus.

The eye is a remarkable organ that allows us to perceive and interact with our surroundings. Various medical specialties, such as ophthalmology and optometry, are dedicated to the diagnosis, treatment, and management of various eye conditions and diseases.

Diplopia is a medical term that refers to the condition where a person sees two images of a single object. It is commonly known as double vision. This can occur due to various reasons, such as nerve damage or misalignment of the eyes. Diplopia can be temporary or chronic and can affect one or both eyes. If you're experiencing diplopia, it's essential to consult an eye care professional for proper evaluation and treatment.

A scotoma is a blind spot or area of reduced vision within the visual field. It's often surrounded by an area of less distinct vision and can be caused by various conditions such as eye diseases, neurological disorders, or brain injuries. A scotoma may be temporary or permanent, depending on its underlying cause.

There are different types of scotomas, including:

1. Central scotoma - a blind spot in the center of the visual field, often associated with conditions like age-related macular degeneration and diabetic retinopathy.
2. Paracentral scotoma - a blind spot located slightly away from the center of the visual field, which can be caused by optic neuritis or other optic nerve disorders.
3. Peripheral scotoma - a blind spot in the peripheral vision, often associated with retinal diseases like retinitis pigmentosa.
4. Absolute scotoma - a complete loss of vision in a specific area of the visual field.
5. Relative scotoma - a partial loss of vision in which some details can still be perceived, but not as clearly or vividly as in normal vision.

It is essential to consult an eye care professional if you experience any changes in your vision or notice a scotoma, as early detection and treatment can help prevent further vision loss.

Demyelinating diseases are a group of disorders that are characterized by damage to the myelin sheath, which is the protective covering surrounding nerve fibers in the brain, optic nerves, and spinal cord. Myelin is essential for the rapid transmission of nerve impulses, and its damage results in disrupted communication between the brain and other parts of the body.

The most common demyelinating disease is multiple sclerosis (MS), where the immune system mistakenly attacks the myelin sheath. Other demyelinating diseases include:

1. Acute Disseminated Encephalomyelitis (ADEM): An autoimmune disorder that typically follows a viral infection or vaccination, causing widespread inflammation and demyelination in the brain and spinal cord.
2. Neuromyelitis Optica (NMO) or Devic's Disease: A rare autoimmune disorder that primarily affects the optic nerves and spinal cord, leading to severe vision loss and motor disability.
3. Transverse Myelitis: Inflammation of the spinal cord causing damage to both sides of one level (segment) of the spinal cord, resulting in various neurological symptoms such as muscle weakness, numbness, or pain, depending on which part of the spinal cord is affected.
4. Guillain-Barré Syndrome: An autoimmune disorder that causes rapid-onset muscle weakness, often beginning in the legs and spreading to the upper body, including the face and breathing muscles. It occurs when the immune system attacks the peripheral nerves' myelin sheath.
5. Central Pontine Myelinolysis (CPM): A rare neurological disorder caused by rapid shifts in sodium levels in the blood, leading to damage to the myelin sheath in a specific area of the brainstem called the pons.

These diseases can result in various symptoms, such as muscle weakness, numbness, vision loss, difficulty with balance and coordination, and cognitive impairment, depending on the location and extent of the demyelination. Treatment typically focuses on managing symptoms, modifying the immune system's response, and promoting nerve regeneration and remyelination when possible.

A point mutation is a type of genetic mutation where a single nucleotide base (A, T, C, or G) in DNA is altered, deleted, or substituted with another nucleotide. Point mutations can have various effects on the organism, depending on the location of the mutation and whether it affects the function of any genes. Some point mutations may not have any noticeable effect, while others might lead to changes in the amino acids that make up proteins, potentially causing diseases or altering traits. Point mutations can occur spontaneously due to errors during DNA replication or be inherited from parents.

Eye diseases are a range of conditions that affect the eye or visual system, causing damage to vision and, in some cases, leading to blindness. These diseases can be categorized into various types, including:

1. Refractive errors: These include myopia (nearsightedness), hyperopia (farsightedness), astigmatism, and presbyopia, which affect the way light is focused on the retina and can usually be corrected with glasses or contact lenses.
2. Cataracts: A clouding of the lens inside the eye that leads to blurry vision, glare, and decreased contrast sensitivity. Cataract surgery is the most common treatment for this condition.
3. Glaucoma: A group of diseases characterized by increased pressure in the eye, leading to damage to the optic nerve and potential blindness if left untreated. Treatment includes medications, laser therapy, or surgery.
4. Age-related macular degeneration (AMD): A progressive condition that affects the central part of the retina called the macula, causing blurry vision and, in advanced stages, loss of central vision. Treatment may include anti-VEGF injections, laser therapy, or nutritional supplements.
5. Diabetic retinopathy: A complication of diabetes that affects the blood vessels in the retina, leading to bleeding, leakage, and potential blindness if left untreated. Treatment includes laser therapy, anti-VEGF injections, or surgery.
6. Retinal detachment: A separation of the retina from its underlying tissue, which can lead to vision loss if not treated promptly with surgery.
7. Amblyopia (lazy eye): A condition where one eye does not develop normal vision, often due to a misalignment or refractive error in childhood. Treatment includes correcting the underlying problem and encouraging the use of the weaker eye through patching or other methods.
8. Strabismus (crossed eyes): A misalignment of the eyes that can lead to amblyopia if not treated promptly with surgery, glasses, or other methods.
9. Corneal diseases: Conditions that affect the transparent outer layer of the eye, such as keratoconus, Fuchs' dystrophy, and infectious keratitis, which can lead to vision loss if not treated promptly.
10. Uveitis: Inflammation of the middle layer of the eye, which can cause vision loss if not treated promptly with anti-inflammatory medications or surgery.

Ethambutol is an antimycobacterial medication used for the treatment of tuberculosis (TB). It works by inhibiting the synthesis of mycobacterial cell walls, which leads to the death of the bacteria. Ethambutol is often used in combination with other TB drugs, such as isoniazid and rifampin, to prevent the development of drug-resistant strains of the bacteria.

The most common side effect of ethambutol is optic neuritis, which can cause visual disturbances such as decreased vision, color blindness, or blurred vision. This side effect is usually reversible if the medication is stopped promptly. Other potential side effects include skin rashes, joint pain, and gastrointestinal symptoms such as nausea and vomiting.

Ethambutol is available in oral tablet and solution forms, and is typically taken once or twice daily. The dosage of ethambutol is based on the patient's weight, and it is important to follow the healthcare provider's instructions carefully to avoid toxicity. Regular monitoring of visual acuity and liver function is recommended during treatment with ethambutol.

Color vision defects, also known as color blindness, are conditions in which a person has difficulty distinguishing between certain colors. The most common types of color vision defects involve the inability to distinguish between red and green or blue and yellow. These deficiencies result from an alteration or absence of one or more of the three types of cone cells in the retina that are responsible for normal color vision.

In red-green color vision defects, there is a problem with either the red or green cones, or both. This results in difficulty distinguishing between these two colors and their shades. Protanopia is a type of red-green color vision defect where there is an absence of red cone cells, making it difficult to distinguish between red and green as well as between red and black or green and black. Deuteranopia is another type of red-green color vision defect where there is an absence of green cone cells, resulting in similar difficulties distinguishing between red and green, as well as between blue and yellow.

Blue-yellow color vision defects are less common than red-green color vision defects. Tritanopia is a type of blue-yellow color vision defect where there is an absence of blue cone cells, making it difficult to distinguish between blue and yellow, as well as between blue and purple or yellow and pink.

Color vision defects are usually inherited and present from birth, but they can also result from eye diseases, chemical exposure, aging, or medication side effects. They affect both men and women, although red-green color vision defects are more common in men than in women. People with color vision defects may have difficulty with tasks that require color discrimination, such as matching clothes, selecting ripe fruit, reading colored maps, or identifying warning signals. However, most people with mild to moderate color vision defects can adapt and function well in daily life.

Nerve degeneration, also known as neurodegeneration, is the progressive loss of structure and function of neurons, which can lead to cognitive decline, motor impairment, and various other symptoms. This process occurs due to a variety of factors, including genetics, environmental influences, and aging. It is a key feature in several neurological disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. The degeneration can affect any part of the nervous system, leading to different symptoms depending on the location and extent of the damage.

Femoral neuropathy is a medical condition that affects the femoral nerve, which is one of the largest nerves in the body. It originates from the lumbar plexus in the lower back and supplies sensation to the front of the thigh and controls the muscles that help straighten the leg and move the knee.

Femoral neuropathy can result from various causes, including nerve compression, trauma, diabetes, tumors, or surgical injury. The symptoms of femoral neuropathy may include numbness, tingling, or weakness in the thigh, difficulty lifting the leg or walking, and decreased knee reflexes.

Diagnosis of femoral neuropathy typically involves a physical examination, medical history, and diagnostic tests such as nerve conduction studies or an MRI to identify any underlying causes. Treatment for femoral neuropathy depends on the cause but may include physical therapy, pain management, and in some cases, surgery.

GTP (Guanosine Triphosphate) Phosphohydrolases are a group of enzymes that catalyze the hydrolysis of GTP to GDP (Guanosine Diphosphate) and inorganic phosphate. This reaction plays a crucial role in regulating various cellular processes, including signal transduction pathways, protein synthesis, and vesicle trafficking.

The human genome encodes several different types of GTP Phosphohydrolases, such as GTPase-activating proteins (GAPs), GTPase effectors, and G protein-coupled receptors (GPCRs). These enzymes share a common mechanism of action, in which they utilize the energy released from GTP hydrolysis to drive conformational changes that enable them to interact with downstream effector molecules and modulate their activity.

Dysregulation of GTP Phosphohydrolases has been implicated in various human diseases, including cancer, neurodegenerative disorders, and infectious diseases. Therefore, understanding the structure, function, and regulation of these enzymes is essential for developing novel therapeutic strategies to target these conditions.

Hemianopsia is a medical term that refers to a loss of vision in half of the visual field in one or both eyes. It can be either homonymous (the same side in both eyes) or heteronymous (different sides in each eye). Hemianopsia usually results from damage to the optic radiations or occipital cortex in the brain, often due to stroke, trauma, tumor, or other neurological conditions. It can significantly impact a person's daily functioning and may require visual rehabilitation to help compensate for the vision loss.

Panuveitis is a medical term that refers to inflammation that affects the entire uveal tract, including the iris, ciliary body, and choroid. The uveal tract is the middle layer of the eye between the inner retina and the outer fibrous tunic (sclera). Panuveitis can also affect other parts of the eye, such as the vitreous, retina, and optic nerve.

The symptoms of panuveitis may include redness, pain, light sensitivity, blurred vision, floaters, and decreased visual acuity. The condition can be caused by various factors, including infections, autoimmune diseases, trauma, or unknown causes (idiopathic). Treatment typically involves the use of corticosteroids to reduce inflammation, as well as addressing any underlying cause if identified. If left untreated, panuveitis can lead to complications such as cataracts, glaucoma, and retinal damage, which can result in permanent vision loss.

Ocular tonometry is a medical test used to measure the pressure inside the eye, also known as intraocular pressure (IOP). This test is an essential part of diagnosing and monitoring glaucoma, a group of eye conditions that can cause vision loss and blindness due to damage to the optic nerve from high IOP.

The most common method of ocular tonometry involves using a tonometer device that gently touches the front surface of the eye (cornea) with a small probe or prism. The device measures the amount of force required to flatten the cornea slightly, which correlates with the pressure inside the eye. Other methods of ocular tonometry include applanation tonometry, which uses a small amount of fluorescein dye and a blue light to measure the IOP, and rebound tonometry, which uses a lightweight probe that briefly touches the cornea and then bounces back to determine the IOP.

Regular ocular tonometry is important for detecting glaucoma early and preventing vision loss. It is typically performed during routine eye exams and may be recommended more frequently for individuals at higher risk of developing glaucoma, such as those with a family history of the condition or certain medical conditions like diabetes.

Choroiditis is an inflammatory condition that affects the choroid, a layer of blood vessels in the eye located between the retina (the light-sensitive tissue at the back of the eye) and the sclera (the white outer coat of the eye). The choroid provides oxygen and nutrients to the outer layers of the retina.

Choroiditis is characterized by spots or patches of inflammation in the choroid, which can lead to damage and scarring of the tissue. This can result in vision loss if it affects the macula (the central part of the retina responsible for sharp, detailed vision). Symptoms of choroiditis may include blurred vision, floaters, sensitivity to light, and decreased color perception.

There are several types of choroiditis, including:

1. Multifocal choroiditis: This type is characterized by multiple, small areas of inflammation in the choroid, often accompanied by scarring. It can affect both eyes and may cause vision loss if it involves the macula.
2. Serpiginous choroiditis: This is a chronic, relapsing form of choroiditis that affects the outer layers of the retina and the choroid. It typically causes well-defined, wavy or serpentine-shaped lesions in the posterior pole (the back part) of the eye.
3. Birdshot chorioretinopathy: This is a rare form of choroiditis that primarily affects the peripheral retina and choroid. It is characterized by multiple, cream-colored or yellowish spots throughout the fundus (the interior surface of the eye).
4. Sympathetic ophthalmia: This is a rare condition that occurs when one eye is injured, leading to inflammation in both eyes. The choroid and other structures in the uninjured eye become inflamed due to an autoimmune response.
5. Vogt-Koyanagi-Harada (VKH) disease: This is a multisystemic autoimmune disorder that affects the eyes, skin, hair, and inner ear. In the eye, it causes choroiditis, retinal inflammation, and sometimes optic nerve swelling.

Treatment for choroiditis depends on the underlying cause and may include corticosteroids, immunosuppressive medications, or biologic agents to control inflammation. In some cases, laser therapy or surgery might be necessary to address complications such as retinal detachment or cataracts.

A mucocele is a mucus-containing cystic lesion that results from the accumulation of mucin within a damaged minor salivary gland duct or mucous gland. It is typically caused by trauma, injury, or blockage of the duct. Mucocele appears as a round, dome-shaped, fluid-filled swelling, which may be bluish or clear in color. They are most commonly found on the lower lip but can also occur on other areas of the oral cavity. Mucocele is generally painless unless it becomes secondarily infected; however, it can cause discomfort during speaking, chewing, or swallowing, and may affect aesthetics. Treatment usually involves surgical excision of the mucocele to prevent recurrence.

Electroretinography (ERG) is a medical test used to evaluate the functioning of the retina, which is the light-sensitive tissue located at the back of the eye. The test measures the electrical responses of the retina to light stimulation.

During the procedure, a special contact lens or electrode is placed on the surface of the eye to record the electrical activity generated by the retina's light-sensitive cells (rods and cones) and other cells in the retina. The test typically involves presenting different levels of flashes of light to the eye while the electrical responses are recorded.

The resulting ERG waveform provides information about the overall health and function of the retina, including the condition of the photoreceptors, the integrity of the inner retinal layers, and the health of the retinal ganglion cells. This test is often used to diagnose and monitor various retinal disorders, such as retinitis pigmentosa, macular degeneration, and diabetic retinopathy.

Rose Bengal is not a medical term per se, but a chemical compound that is used in various medical applications. It's a dye that is primarily used as a diagnostic stain to test for damaged or denatured cells, particularly in the eye and mouth. In ophthalmology, a Rose Bengal stain is used to identify damage to the cornea's surface, while in dentistry, it can help detect injured oral mucosa or lesions.

The dye works by staining dead or damaged cells more intensely than healthy ones, allowing healthcare professionals to visualize and assess any abnormalities or injuries. However, it is important to note that Rose Bengal itself is not a treatment for these conditions; rather, it is a diagnostic tool used to inform appropriate medical interventions.

Mitochondrial genes are a type of gene that is located in the DNA (deoxyribonucleic acid) found in the mitochondria, which are small organelles present in the cytoplasm of eukaryotic cells (cells with a true nucleus). Mitochondria are responsible for generating energy for the cell through a process called oxidative phosphorylation.

The human mitochondrial genome is a circular DNA molecule that contains 37 genes, including 13 genes that encode for proteins involved in oxidative phosphorylation, 22 genes that encode for transfer RNAs (tRNAs), and 2 genes that encode for ribosomal RNAs (rRNAs). Mutations in mitochondrial genes can lead to a variety of inherited mitochondrial disorders, which can affect any organ system in the body and can present at any age.

Mitochondrial DNA is maternally inherited, meaning that it is passed down from the mother to her offspring through the egg cell. This is because during fertilization, only the sperm's nucleus enters the egg, while the mitochondria remain outside. As a result, all of an individual's mitochondrial DNA comes from their mother.

Median neuropathy, also known as Carpal Tunnel Syndrome, is a common entrapment neuropathy caused by compression of the median nerve at the wrist level. The median nerve provides sensation to the palm side of the thumb, index finger, middle finger, and half of the ring finger. It also innervates some of the muscles that control movement of the fingers and thumb.

In median neuropathy, the compression of the median nerve can cause symptoms such as numbness, tingling, and weakness in the affected hand and fingers. These symptoms may be worse at night or upon waking up in the morning, and can be exacerbated by activities that involve repetitive motion of the wrist, such as typing or using tools. If left untreated, median neuropathy can lead to permanent nerve damage and muscle wasting in the hand.

DNA probes for HLA (Human Leukocyte Antigen) are specific DNA sequences that are used in laboratory tests to detect and identify the presence or absence of particular HLA genes or alleles in an individual's genetic material. HLAs are proteins found on the surface of cells that play a critical role in the immune system's ability to distinguish between "self" and "non-self."

DNA probes for HLA are typically composed of short, single-stranded DNA molecules that are complementary to a specific region of the HLA gene. These probes are labeled with a detectable marker, such as a radioactive isotope or a fluorescent dye, allowing them to be visualized and detected during laboratory testing.

When a DNA probe for HLA is hybridized to a sample of an individual's genetic material, it will bind specifically to the complementary sequence of the target HLA gene, if present. The presence or absence of the probe-target hybrid can then be detected and used to identify the specific HLA allele.

DNA probes for HLA are used in a variety of applications, including diagnostic testing, tissue typing for transplantation, and research into the genetic basis of diseases that are associated with particular HLA types.

Peripheral nerves are nerve fibers that transmit signals between the central nervous system (CNS, consisting of the brain and spinal cord) and the rest of the body. These nerves convey motor, sensory, and autonomic information, enabling us to move, feel, and respond to changes in our environment. They form a complex network that extends from the CNS to muscles, glands, skin, and internal organs, allowing for coordinated responses and functions throughout the body. Damage or injury to peripheral nerves can result in various neurological symptoms, such as numbness, weakness, or pain, depending on the type and severity of the damage.

Mitochondria are specialized structures located inside cells that convert the energy from food into ATP (adenosine triphosphate), which is the primary form of energy used by cells. They are often referred to as the "powerhouses" of the cell because they generate most of the cell's supply of chemical energy. Mitochondria are also involved in various other cellular processes, such as signaling, differentiation, and apoptosis (programmed cell death).

Mitochondria have their own DNA, known as mitochondrial DNA (mtDNA), which is inherited maternally. This means that mtDNA is passed down from the mother to her offspring through the egg cells. Mitochondrial dysfunction has been linked to a variety of diseases and conditions, including neurodegenerative disorders, diabetes, and aging.

Animal disease models are specialized animals, typically rodents such as mice or rats, that have been genetically engineered or exposed to certain conditions to develop symptoms and physiological changes similar to those seen in human diseases. These models are used in medical research to study the pathophysiology of diseases, identify potential therapeutic targets, test drug efficacy and safety, and understand disease mechanisms.

The genetic modifications can include knockout or knock-in mutations, transgenic expression of specific genes, or RNA interference techniques. The animals may also be exposed to environmental factors such as chemicals, radiation, or infectious agents to induce the disease state.

Examples of animal disease models include:

1. Mouse models of cancer: Genetically engineered mice that develop various types of tumors, allowing researchers to study cancer initiation, progression, and metastasis.
2. Alzheimer's disease models: Transgenic mice expressing mutant human genes associated with Alzheimer's disease, which exhibit amyloid plaque formation and cognitive decline.
3. Diabetes models: Obese and diabetic mouse strains like the NOD (non-obese diabetic) or db/db mice, used to study the development of type 1 and type 2 diabetes, respectively.
4. Cardiovascular disease models: Atherosclerosis-prone mice, such as ApoE-deficient or LDLR-deficient mice, that develop plaque buildup in their arteries when fed a high-fat diet.
5. Inflammatory bowel disease models: Mice with genetic mutations affecting intestinal barrier function and immune response, such as IL-10 knockout or SAMP1/YitFc mice, which develop colitis.

Animal disease models are essential tools in preclinical research, but it is important to recognize their limitations. Differences between species can affect the translatability of results from animal studies to human patients. Therefore, researchers must carefully consider the choice of model and interpret findings cautiously when applying them to human diseases.

Low vision is a term used to describe significant visual impairment that cannot be corrected with standard glasses, contact lenses, medication or surgery. It is typically defined as visual acuity of less than 20/70 in the better-seeing eye after best correction, or a visual field of less than 20 degrees in the better-seeing eye.

People with low vision may have difficulty performing everyday tasks such as reading, recognizing faces, watching television, driving, or simply navigating their environment. They may also experience symptoms such as sensitivity to light, glare, or contrast, and may benefit from the use of visual aids, assistive devices, and rehabilitation services to help them maximize their remaining vision and maintain their independence.

Low vision can result from a variety of causes, including eye diseases such as macular degeneration, diabetic retinopathy, glaucoma, or cataracts, as well as congenital or inherited conditions, brain injuries, or aging. It is important for individuals with low vision to receive regular eye examinations and consult with a low vision specialist to determine the best course of treatment and management.

Ophthalmologic surgical procedures refer to various types of surgeries performed on the eye and its surrounding structures by trained medical professionals called ophthalmologists. These procedures aim to correct or improve vision, diagnose and treat eye diseases or injuries, and enhance the overall health and functionality of the eye. Some common examples of ophthalmologic surgical procedures include:

1. Cataract Surgery: This procedure involves removing a cloudy lens (cataract) from the eye and replacing it with an artificial intraocular lens (IOL).
2. LASIK (Laser-Assisted In Situ Keratomileusis): A type of refractive surgery that uses a laser to reshape the cornea, correcting nearsightedness, farsightedness, and astigmatism.
3. Glaucoma Surgery: Several surgical options are available for treating glaucoma, including laser trabeculoplasty, traditional trabeculectomy, and various drainage device implantations. These procedures aim to reduce intraocular pressure (IOP) and prevent further optic nerve damage.
4. Corneal Transplant: This procedure involves replacing a damaged or diseased cornea with a healthy donor cornea to restore vision and improve the eye's appearance.
5. Vitreoretinal Surgery: These procedures focus on treating issues within the vitreous humor (gel-like substance filling the eye) and the retina, such as retinal detachment, macular holes, or diabetic retinopathy.
6. Strabismus Surgery: This procedure aims to correct misalignment of the eyes (strabismus) by adjusting the muscles responsible for eye movement.
7. Oculoplastic Surgery: These procedures involve reconstructive, cosmetic, and functional surgeries around the eye, such as eyelid repair, removal of tumors, or orbital fracture repairs.
8. Pediatric Ophthalmologic Procedures: Various surgical interventions are performed on children to treat conditions like congenital cataracts, amblyopia (lazy eye), or blocked tear ducts.

These are just a few examples of ophthalmic surgical procedures. The specific treatment plan will depend on the individual's condition and overall health.

Neuromyelitis optica (NMO), also known as Devic's disease, is an autoimmune disorder that affects the central nervous system (CNS). It primarily causes inflammation and damage to the optic nerves (which transmit visual signals from the eye to the brain) and the spinal cord. This results in optic neuritis (inflammation of the optic nerve, causing vision loss) and myelitis (inflammation of the spinal cord, leading to motor, sensory, and autonomic dysfunction).

A key feature of NMO is the presence of autoantibodies against aquaporin-4 (AQP4-IgG), a water channel protein found in astrocytes (a type of glial cell) in the CNS. These antibodies play a crucial role in the development of the disease, as they target and damage the AQP4 proteins, leading to inflammation, demyelination (loss of the protective myelin sheath around nerve fibers), and subsequent neurological dysfunction.

NMO is distinct from multiple sclerosis (MS), another autoimmune disorder affecting the CNS, as it has different clinical features, radiological findings, and treatment responses. However, NMO can sometimes be misdiagnosed as MS due to overlapping symptoms in some cases. Accurate diagnosis of NMO is essential for appropriate management and treatment, which often includes immunosuppressive therapies to control the autoimmune response and prevent further damage to the nervous system.

Medical Definition:

Magnetic Resonance Imaging (MRI) is a non-invasive diagnostic imaging technique that uses a strong magnetic field and radio waves to create detailed cross-sectional or three-dimensional images of the internal structures of the body. The patient lies within a large, cylindrical magnet, and the scanner detects changes in the direction of the magnetic field caused by protons in the body. These changes are then converted into detailed images that help medical professionals to diagnose and monitor various medical conditions, such as tumors, injuries, or diseases affecting the brain, spinal cord, heart, blood vessels, joints, and other internal organs. MRI does not use radiation like computed tomography (CT) scans.

Amyloid neuropathies are a group of peripheral nerve disorders caused by the abnormal accumulation of amyloid proteins in the nerves. Amyloid is a protein that can be produced in various diseases and can deposit in different organs, including nerves. When this occurs in the nerves, it can lead to damage and dysfunction, resulting in symptoms such as numbness, tingling, pain, and weakness in the affected limbs.

There are several types of amyloid neuropathies, with the two most common being:

1. Transthyretin (TTR)-related hereditary amyloidosis: This is an inherited disorder caused by mutations in the TTR gene, which leads to the production of abnormal TTR protein that can form amyloid deposits in various organs, including nerves.
2. Immunoglobulin light chain (AL) amyloidosis: This is a disorder in which abnormal plasma cells produce excessive amounts of immunoglobulin light chains, which can form amyloid deposits in various organs, including nerves.

The diagnosis of amyloid neuropathies typically involves a combination of clinical evaluation, nerve conduction studies, and tissue biopsy to confirm the presence of amyloid deposits. Treatment options depend on the underlying cause of the disorder and may include medications, chemotherapy, stem cell transplantation, or supportive care to manage symptoms.

Graves' disease is defined as an autoimmune disorder that leads to overactivity of the thyroid gland (hyperthyroidism). It results when the immune system produces antibodies that stimulate the thyroid gland, causing it to produce too much thyroid hormone. This can result in a variety of symptoms such as rapid heartbeat, weight loss, heat intolerance, and bulging eyes (Graves' ophthalmopathy). The exact cause of Graves' disease is unknown, but it is more common in women and people with a family history of the disorder. Treatment may include medications to control hyperthyroidism, radioactive iodine therapy to destroy thyroid tissue, or surgery to remove the thyroid gland.

Exophthalmos is a medical condition that refers to the abnormal protrusion or bulging of one or both eyes beyond the normal orbit (eye socket). This condition is also known as proptosis. Exophthalmos can be caused by various factors, including thyroid eye disease (Graves' ophthalmopathy), tumors, inflammation, trauma, or congenital abnormalities. It can lead to various symptoms such as double vision, eye discomfort, redness, and difficulty closing the eyes. Treatment of exophthalmos depends on the underlying cause and may include medications, surgery, or radiation therapy.

Ischemia is the medical term used to describe a lack of blood flow to a part of the body, often due to blocked or narrowed blood vessels. This can lead to a shortage of oxygen and nutrients in the tissues, which can cause them to become damaged or die. Ischemia can affect many different parts of the body, including the heart, brain, legs, and intestines. Symptoms of ischemia depend on the location and severity of the blockage, but they may include pain, cramping, numbness, weakness, or coldness in the affected area. In severe cases, ischemia can lead to tissue death (gangrene) or organ failure. Treatment for ischemia typically involves addressing the underlying cause of the blocked blood flow, such as through medication, surgery, or lifestyle changes.

Paranasal sinus diseases refer to a group of medical conditions that affect the paranasal sinuses, which are air-filled cavities located within the skull near the nasal cavity. These sinuses include the maxillary, frontal, ethmoid, and sphenoid sinuses.

Paranasal sinus diseases can be caused by a variety of factors, including viral, bacterial, or fungal infections, allergies, structural abnormalities, or autoimmune disorders. Some common paranasal sinus diseases include:

1. Sinusitis: Inflammation or infection of the sinuses, which can cause symptoms such as nasal congestion, thick nasal discharge, facial pain or pressure, and reduced sense of smell.
2. Nasal polyps: Soft, benign growths that develop in the lining of the nasal passages or sinuses, which can obstruct airflow and cause difficulty breathing through the nose.
3. Sinonasal tumors: Abnormal growths that can be benign or malignant, which can cause symptoms such as nasal congestion, facial pain, and bleeding from the nose.
4. Sinus cysts: Fluid-filled sacs that form in the sinuses, which can cause symptoms similar to those of sinusitis.
5. Fungal sinusitis: Infection of the sinuses with fungi, which can cause symptoms such as nasal congestion, facial pain, and thick, discolored mucus.

Treatment for paranasal sinus diseases depends on the underlying cause and severity of the condition. Treatment options may include medications, such as antibiotics, antihistamines, or corticosteroids, as well as surgical intervention in more severe cases.

Infarction is the term used in medicine to describe the death of tissue (also known as an "area of necrosis") due to the lack of blood supply. This can occur when a blood vessel that supplies oxygen and nutrients to a particular area of the body becomes blocked or obstructed, leading to the deprivation of oxygen and nutrients necessary for the survival of cells in that region.

The blockage in the blood vessel is usually caused by a clot (thrombus) or an embolus, which is a small particle that travels through the bloodstream and lodges in a smaller vessel. The severity and extent of infarction depend on several factors, including the size and location of the affected blood vessel, the duration of the obstruction, and the presence of collateral circulation (alternative blood vessels that can compensate for the blocked one).

Common examples of infarctions include myocardial infarction (heart attack), cerebral infarction (stroke), and pulmonary infarction (lung tissue death due to obstruction in the lung's blood vessels). Infarctions can lead to various symptoms, depending on the affected organ or tissue, and may require medical intervention to manage complications and prevent further damage.

Cranial nerve diseases refer to conditions that affect the cranial nerves, which are a set of 12 pairs of nerves that originate from the brainstem and control various functions in the head and neck. These functions include vision, hearing, taste, smell, movement of the eyes and face, and sensation in the face.

Diseases of the cranial nerves can result from a variety of causes, including injury, infection, inflammation, tumors, or degenerative conditions. The specific symptoms that a person experiences will depend on which cranial nerve is affected and how severely it is damaged.

For example, damage to the optic nerve (cranial nerve II) can cause vision loss or visual disturbances, while damage to the facial nerve (cranial nerve VII) can result in weakness or paralysis of the face. Other common symptoms of cranial nerve diseases include pain, numbness, tingling, and hearing loss.

Treatment for cranial nerve diseases varies depending on the underlying cause and severity of the condition. In some cases, medication or surgery may be necessary to treat the underlying cause and relieve symptoms. Physical therapy or rehabilitation may also be recommended to help individuals regain function and improve their quality of life.

A haplotype is a group of genes or DNA sequences that are inherited together from a single parent. It refers to a combination of alleles (variant forms of a gene) that are located on the same chromosome and are usually transmitted as a unit. Haplotypes can be useful in tracing genetic ancestry, understanding the genetic basis of diseases, and developing personalized medical treatments.

In population genetics, haplotypes are often used to study patterns of genetic variation within and between populations. By comparing haplotype frequencies across populations, researchers can infer historical events such as migrations, population expansions, and bottlenecks. Additionally, haplotypes can provide information about the evolutionary history of genes and genomic regions.

In clinical genetics, haplotypes can be used to identify genetic risk factors for diseases or to predict an individual's response to certain medications. For example, specific haplotypes in the HLA gene region have been associated with increased susceptibility to certain autoimmune diseases, while other haplotypes in the CYP450 gene family can affect how individuals metabolize drugs.

Overall, haplotypes provide a powerful tool for understanding the genetic basis of complex traits and diseases, as well as for developing personalized medical treatments based on an individual's genetic makeup.

Temporal arteries are the paired set of arteries that run along the temples on either side of the head. They are branches of the external carotid artery and play a crucial role in supplying oxygenated blood to the scalp and surrounding muscles. One of the most common conditions associated with temporal arteries is Temporal Arteritis (also known as Giant Cell Arteritis), which is an inflammation of these arteries that can lead to serious complications like vision loss if not promptly diagnosed and treated.

Visual pathways, also known as the visual system or the optic pathway, refer to the series of specialized neurons in the nervous system that transmit visual information from the eyes to the brain. This complex network includes the retina, optic nerve, optic chiasma, optic tract, lateral geniculate nucleus, pulvinar, and the primary and secondary visual cortices located in the occipital lobe of the brain.

The process begins when light enters the eye and strikes the photoreceptor cells (rods and cones) in the retina, converting the light energy into electrical signals. These signals are then transmitted to bipolar cells and subsequently to ganglion cells, whose axons form the optic nerve. The fibers from each eye's nasal hemiretina cross at the optic chiasma, while those from the temporal hemiretina continue without crossing. This results in the formation of the optic tract, which carries visual information from both eyes to the opposite side of the brain.

The majority of fibers in the optic tract synapse with neurons in the lateral geniculate nucleus (LGN), a part of the thalamus. The LGN sends this information to the primary visual cortex, also known as V1 or Brodmann area 17, located in the occipital lobe. Here, simple features like lines and edges are initially processed. Further processing occurs in secondary (V2) and tertiary (V3-V5) visual cortices, where more complex features such as shape, motion, and depth are analyzed. Ultimately, this information is integrated to form our perception of the visual world.

The sciatic nerve is the largest and longest nerve in the human body, running from the lower back through the buttocks and down the legs to the feet. It is formed by the union of the ventral rami (branches) of the L4 to S3 spinal nerves. The sciatic nerve provides motor and sensory innervation to various muscles and skin areas in the lower limbs, including the hamstrings, calf muscles, and the sole of the foot. Sciatic nerve disorders or injuries can result in symptoms such as pain, numbness, tingling, or weakness in the lower back, hips, legs, and feet, known as sciatica.

Angle-closure glaucoma is a type of glaucoma that is characterized by the sudden or gradually increasing pressure in the eye (intraocular pressure) due to the closure or narrowing of the angle between the iris and cornea. This angle is where the drainage system of the eye, called the trabecular meshwork, is located. When the angle becomes too narrow or closes completely, fluid cannot properly drain from the eye, leading to a buildup of pressure that can damage the optic nerve and cause permanent vision loss.

Angle-closure glaucoma can be either acute or chronic. Acute angle-closure glaucoma is a medical emergency that requires immediate treatment to prevent permanent vision loss. It is characterized by sudden symptoms such as severe eye pain, nausea and vomiting, blurred vision, halos around lights, and redness of the eye.

Chronic angle-closure glaucoma, on the other hand, develops more slowly over time and may not have any noticeable symptoms until significant damage has already occurred. It is important to diagnose and treat angle-closure glaucoma as early as possible to prevent vision loss. Treatment options include medications to lower eye pressure, laser treatment to create a new opening for fluid drainage, or surgery to improve the flow of fluid out of the eye.

Color perception tests are a type of examination used to evaluate an individual's ability to perceive and distinguish different colors. These tests typically consist of a series of plates or images that contain various patterns or shapes displayed in different colors. The person being tested is then asked to identify or match the colors based on specific instructions.

There are several types of color perception tests, including:

1. Ishihara Test: This is a commonly used test for red-green color deficiency. It consists of a series of plates with circles made up of dots in different sizes and colors. Within these circles, there may be a number or symbol visible only to those with normal color vision or to those with specific types of color blindness.
2. Farnsworth D-15 Test: This test measures an individual's ability to arrange colored caps in a specific order based on their hue. It is often used to diagnose and monitor the progression of color vision deficiencies.
3. Hardy-Rand-Rittler (HRR) Test: This is another type of color arrangement test that measures an individual's ability to distinguish between different colors based on their hue, saturation, and brightness.
4. Color Discrimination Tests: These tests measure an individual's ability to distinguish between two similar colors that are presented side by side or in close proximity.
5. Anomaloscope Test: This is a more sophisticated test that measures the degree of color vision deficiency by asking the person to match the brightness and hue of two lights.

Color perception tests are often used in occupational settings, such as aviation, military, and manufacturing, where color discrimination is critical for safety and performance. They may also be used in educational and clinical settings to diagnose and monitor color vision deficiencies.

Multiple Sclerosis (MS) is a chronic autoimmune disease that affects the central nervous system (CNS), which includes the brain, spinal cord, and optic nerves. In MS, the immune system mistakenly attacks the protective covering of nerve fibers, called myelin, leading to damage and scarring (sclerosis). This results in disrupted communication between the brain and the rest of the body, causing a variety of neurological symptoms that can vary widely from person to person.

The term "multiple" refers to the numerous areas of scarring that occur throughout the CNS in this condition. The progression, severity, and specific symptoms of MS are unpredictable and may include vision problems, muscle weakness, numbness or tingling, difficulty with balance and coordination, cognitive impairment, and mood changes. There is currently no cure for MS, but various treatments can help manage symptoms, modify the course of the disease, and improve quality of life for those affected.

Low tension glaucoma, also known as normal tension glaucoma, is a type of glaucoma characterized by optic nerve damage and visual field loss in the absence of consistently elevated intraocular pressure (IOP). In this form of glaucoma, the IOP typically remains within the statistically normal range, which is generally defined as below 21 mmHg. However, some individuals may have an IOP that is considered "low tension" for their specific optic nerve susceptibility.

The exact cause of low tension glaucoma remains unclear, but it is thought to involve factors such as impaired blood flow to the optic nerve, genetic predisposition, and sensitivity to minor fluctuations in IOP. People with low tension glaucoma may require close monitoring and management, including regular IOP checks, visual field testing, and sometimes the use of medications or surgical interventions to reduce the risk of further optic nerve damage and vision loss.

Eye pain is defined as discomfort or unpleasant sensations in the eye. It can be sharp, throbbing, stabbing, burning, or aching. The pain may occur in one or both eyes and can range from mild to severe. Eye pain can result from various causes, including infection, inflammation, injury, or irritation of the structures of the eye, such as the cornea, conjunctiva, sclera, or uvea. Other possible causes include migraines, optic neuritis, and glaucoma. It is essential to seek medical attention if experiencing sudden, severe, or persistent eye pain, as it can be a sign of a serious underlying condition that requires prompt treatment.

Retrospective studies, also known as retrospective research or looking back studies, are a type of observational study that examines data from the past to draw conclusions about possible causal relationships between risk factors and outcomes. In these studies, researchers analyze existing records, medical charts, or previously collected data to test a hypothesis or answer a specific research question.

Retrospective studies can be useful for generating hypotheses and identifying trends, but they have limitations compared to prospective studies, which follow participants forward in time from exposure to outcome. Retrospective studies are subject to biases such as recall bias, selection bias, and information bias, which can affect the validity of the results. Therefore, retrospective studies should be interpreted with caution and used primarily to generate hypotheses for further testing in prospective studies.

Ulnar nerve compression syndromes refer to a group of conditions characterized by the entrapment or compression of the ulnar nerve, leading to various symptoms. The ulnar nerve provides motor function to the hand muscles and sensation to the little finger and half of the ring finger.

There are several sites along the course of the ulnar nerve where it can become compressed, resulting in different types of ulnar nerve compression syndromes:

1. Cubital Tunnel Syndrome: This occurs when the ulnar nerve is compressed at the elbow, within the cubital tunnel - a narrow passage located on the inner side of the elbow. Symptoms may include numbness and tingling in the little finger and half of the ring finger, weakness in gripping or pinching, and pain or discomfort in the elbow.

2. Guyon's Canal Syndrome: This type of ulnar nerve compression syndrome happens when the nerve is compressed at the wrist, within the Guyon's canal. Causes can include ganglion cysts, bone fractures, or repetitive motion injuries. Symptoms may include numbness and tingling in the little finger and half of the ring finger, weakness or paralysis in the hand muscles, and muscle wasting in severe cases.

Treatment for ulnar nerve compression syndromes depends on the severity and location of the compression. Conservative treatments such as physical therapy, bracing, or anti-inflammatory medications may be recommended for milder cases. Severe or persistent symptoms may require surgical intervention to relieve the pressure on the ulnar nerve.

An intravitreal injection is a medical procedure in which medication is delivered directly into the vitreous cavity of the eye, which is the clear, gel-like substance that fills the space between the lens and the retina. This type of injection is typically used to treat various eye conditions such as age-related macular degeneration, diabetic retinopathy, retinal vein occlusion, and uveitis. The medication administered in intravitreal injections can help to reduce inflammation, inhibit the growth of new blood vessels, or prevent the formation of abnormal blood vessels in the eye.

Intravitreal injections are usually performed in an outpatient setting, and the procedure typically takes only a few minutes. Before the injection, the eye is numbed with anesthetic drops to minimize discomfort. The medication is then injected into the vitreous cavity using a small needle. After the injection, patients may experience some mild discomfort or a scratchy sensation in the eye, but this usually resolves within a few hours.

While intravitreal injections are generally safe, there are some potential risks and complications associated with the procedure, including infection, bleeding, retinal detachment, and increased intraocular pressure. Patients who undergo intravitreal injections should be closely monitored by their eye care provider to ensure that any complications are promptly identified and treated.

A case-control study is an observational research design used to identify risk factors or causes of a disease or health outcome. In this type of study, individuals with the disease or condition (cases) are compared with similar individuals who do not have the disease or condition (controls). The exposure history or other characteristics of interest are then compared between the two groups to determine if there is an association between the exposure and the disease.

Case-control studies are often used when it is not feasible or ethical to conduct a randomized controlled trial, as they can provide valuable insights into potential causes of diseases or health outcomes in a relatively short period of time and at a lower cost than other study designs. However, because case-control studies rely on retrospective data collection, they are subject to biases such as recall bias and selection bias, which can affect the validity of the results. Therefore, it is important to carefully design and conduct case-control studies to minimize these potential sources of bias.

The "age of onset" is a medical term that refers to the age at which an individual first develops or displays symptoms of a particular disease, disorder, or condition. It can be used to describe various medical conditions, including both physical and mental health disorders. The age of onset can have implications for prognosis, treatment approaches, and potential causes of the condition. In some cases, early onset may indicate a more severe or progressive course of the disease, while late-onset symptoms might be associated with different underlying factors or etiologies. It is essential to provide accurate and precise information regarding the age of onset when discussing a patient's medical history and treatment plan.

Pathological nystagmus is an abnormal, involuntary movement of the eyes that can occur in various directions (horizontal, vertical, or rotatory) and can be rhythmical or arrhythmic. It is typically a result of a disturbance in the vestibular system, central nervous system, or ocular motor pathways. Pathological nystagmus can cause visual symptoms such as blurred vision, difficulty with fixation, and oscillopsia (the sensation that one's surroundings are moving). The type, direction, and intensity of the nystagmus may vary depending on the underlying cause, which can include conditions such as brainstem or cerebellar lesions, multiple sclerosis, drug toxicity, inner ear disorders, and congenital abnormalities.

Electrodiagnosis, also known as electromyography (EMG), is a medical diagnostic procedure that evaluates the health and function of muscles and nerves. It measures the electrical activity of skeletal muscles at rest and during contraction, as well as the conduction of electrical signals along nerves.

The test involves inserting a thin needle electrode into the muscle to record its electrical activity. The physician will ask the patient to contract and relax the muscle while the electrical activity is recorded. The resulting data can help diagnose various neuromuscular disorders, such as nerve damage or muscle diseases, by identifying abnormalities in the electrical signals.

Electrodiagnosis can be used to diagnose conditions such as carpal tunnel syndrome, peripheral neuropathy, muscular dystrophy, and amyotrophic lateral sclerosis (ALS), among others. It is a valuable tool in the diagnosis and management of neuromuscular disorders, helping physicians to develop appropriate treatment plans for their patients.

Follow-up studies are a type of longitudinal research that involve repeated observations or measurements of the same variables over a period of time, in order to understand their long-term effects or outcomes. In medical context, follow-up studies are often used to evaluate the safety and efficacy of medical treatments, interventions, or procedures.

In a typical follow-up study, a group of individuals (called a cohort) who have received a particular treatment or intervention are identified and then followed over time through periodic assessments or data collection. The data collected may include information on clinical outcomes, adverse events, changes in symptoms or functional status, and other relevant measures.

The results of follow-up studies can provide important insights into the long-term benefits and risks of medical interventions, as well as help to identify factors that may influence treatment effectiveness or patient outcomes. However, it is important to note that follow-up studies can be subject to various biases and limitations, such as loss to follow-up, recall bias, and changes in clinical practice over time, which must be carefully considered when interpreting the results.

The ophthalmic artery is the first branch of the internal carotid artery, which supplies blood to the eye and its adnexa. It divides into several branches that provide oxygenated blood to various structures within the eye, including the retina, optic nerve, choroid, iris, ciliary body, and cornea. Any blockage or damage to the ophthalmic artery can lead to serious vision problems or even blindness.

Ubiquinone, also known as coenzyme Q10 (CoQ10), is a lipid-soluble benzoquinone that plays a crucial role in the mitochondrial electron transport chain as an essential component of Complexes I, II, and III. It functions as an electron carrier, assisting in the transfer of electrons from reduced nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FADH2) to molecular oxygen during oxidative phosphorylation, thereby contributing to the generation of adenosine triphosphate (ATP), the primary energy currency of the cell.

Additionally, ubiquinone acts as a potent antioxidant in both membranes and lipoproteins, protecting against lipid peroxidation and oxidative damage to proteins and DNA. Its antioxidant properties stem from its ability to donate electrons and regenerate other antioxidants like vitamin E. Ubiquinone is synthesized endogenously in all human cells, with the highest concentrations found in tissues with high energy demands, such as the heart, liver, kidneys, and skeletal muscles.

Deficiency in ubiquinone can result from genetic disorders, aging, or certain medications (such as statins), leading to impaired mitochondrial function and increased oxidative stress. Supplementation with ubiquinone has been explored as a potential therapeutic strategy for various conditions associated with mitochondrial dysfunction and oxidative stress, including cardiovascular diseases, neurodegenerative disorders, and cancer.

Amiodarone is a Class III antiarrhythmic medication used to treat and prevent various types of irregular heart rhythms (arrhythmias). It works by stabilizing the electrical activity of the heart and slowing down the nerve impulses in the heart tissue. Amiodarone is available in oral tablet and injection forms.

The medical definition of 'Amiodarone' is:

A benzofuran derivative with Class III antiarrhythmic properties, used for the treatment of ventricular arrhythmias. It has a relatively slow onset of action and is therefore not useful in acute situations. Additionally, it has negative inotropic effects and may exacerbate heart failure. The most serious adverse effect is pulmonary fibrosis, which occurs in approximately 1-2% of patients. Other important side effects include corneal microdeposits, hepatotoxicity, thyroid dysfunction, and photosensitivity. Amiodarone has a very long half-life (approximately 50 days) due to its extensive tissue distribution. It is metabolized by the liver and excreted in bile and urine.

Sources:

1. UpToDate - Amiodarone use in adults: Indications, dosing, and adverse effects.
2. Micromedex - Amiodarone.
3. Drugs.com - Amiodarone.

Nervous system diseases, also known as neurological disorders, refer to a group of conditions that affect the nervous system, which includes the brain, spinal cord, nerves, and muscles. These diseases can affect various functions of the body, such as movement, sensation, cognition, and behavior. They can be caused by genetics, infections, injuries, degeneration, or tumors. Examples of nervous system diseases include Alzheimer's disease, Parkinson's disease, multiple sclerosis, epilepsy, migraine, stroke, and neuroinfections like meningitis and encephalitis. The symptoms and severity of these disorders can vary widely, ranging from mild to severe and debilitating.

The term "Asian Continental Ancestry Group" is a medical/ethnic classification used to describe a person's genetic background and ancestry. According to this categorization, individuals with origins in the Asian continent are grouped together. This includes populations from regions such as East Asia (e.g., China, Japan, Korea), South Asia (e.g., India, Pakistan, Bangladesh), Southeast Asia (e.g., Philippines, Indonesia, Thailand), and Central Asia (e.g., Kazakhstan, Uzbekistan, Tajikistan). It is important to note that this broad categorization may not fully capture the genetic diversity within these regions or accurately reflect an individual's specific ancestral origins.

Polymerase Chain Reaction (PCR) is a laboratory technique used to amplify specific regions of DNA. It enables the production of thousands to millions of copies of a particular DNA sequence in a rapid and efficient manner, making it an essential tool in various fields such as molecular biology, medical diagnostics, forensic science, and research.

The PCR process involves repeated cycles of heating and cooling to separate the DNA strands, allow primers (short sequences of single-stranded DNA) to attach to the target regions, and extend these primers using an enzyme called Taq polymerase, resulting in the exponential amplification of the desired DNA segment.

In a medical context, PCR is often used for detecting and quantifying specific pathogens (viruses, bacteria, fungi, or parasites) in clinical samples, identifying genetic mutations or polymorphisms associated with diseases, monitoring disease progression, and evaluating treatment effectiveness.

A pupil, in medical terms, refers to the circular opening in the center of the iris (the colored part of the eye) that allows light to enter and reach the retina. The size of the pupil can change involuntarily in response to light intensity and emotional state, as well as voluntarily through certain eye exercises or with the use of eye drops. Pupillary reactions are important in clinical examinations as they can provide valuable information about the nervous system's functioning, particularly the brainstem and cranial nerves II and III.

Neurological diagnostic techniques are medical tests and examinations used to identify and diagnose conditions related to the nervous system, which includes the brain, spinal cord, nerves, and muscles. These techniques can be divided into several categories:

1. Clinical Examination: A thorough physical examination, including a neurological evaluation, is often the first step in diagnosing neurological conditions. This may involve assessing a person's mental status, muscle strength, coordination, reflexes, sensation, and gait.

2. Imaging Techniques: These are used to produce detailed images of the brain and nervous system. Common imaging techniques include:

- Computed Tomography (CT): This uses X-rays to create cross-sectional images of the brain and other parts of the body.
- Magnetic Resonance Imaging (MRI): This uses a strong magnetic field and radio waves to produce detailed images of the brain and other internal structures.
- Functional MRI (fMRI): This is a type of MRI that measures brain activity by detecting changes in blood flow.
- Positron Emission Tomography (PET): This uses small amounts of radioactive material to produce detailed images of brain function.
- Single Photon Emission Computed Tomography (SPECT): This is a type of nuclear medicine imaging that uses a gamma camera and a computer to produce detailed images of brain function.

3. Electrophysiological Tests: These are used to measure the electrical activity of the brain and nervous system. Common electrophysiological tests include:

- Electroencephalography (EEG): This measures the electrical activity of the brain.
- Evoked Potentials (EPs): These measure the electrical response of the brain and nervous system to sensory stimuli, such as sound or light.
- Nerve Conduction Studies (NCS): These measure the speed and strength of nerve impulses.
- Electromyography (EMG): This measures the electrical activity of muscles.

4. Laboratory Tests: These are used to analyze blood, cerebrospinal fluid, and other bodily fluids for signs of neurological conditions. Common laboratory tests include:

- Complete Blood Count (CBC): This measures the number and type of white and red blood cells in the body.
- Blood Chemistry Tests: These measure the levels of various chemicals in the blood.
- Lumbar Puncture (Spinal Tap): This is used to collect cerebrospinal fluid for analysis.
- Genetic Testing: This is used to identify genetic mutations associated with neurological conditions.

5. Imaging Studies: These are used to produce detailed images of the brain and nervous system. Common imaging studies include:

- Magnetic Resonance Imaging (MRI): This uses a strong magnetic field and radio waves to produce detailed images of the brain and nervous system.
- Computed Tomography (CT): This uses X-rays to produce detailed images of the brain and nervous system.
- Functional MRI (fMRI): This measures changes in blood flow in the brain during cognitive tasks.
- Diffusion Tensor Imaging (DTI): This is used to assess white matter integrity in the brain.
- Magnetic Resonance Spectroscopy (MRS): This is used to measure chemical levels in the brain.

Ethmoid sinusitis is a medical condition that refers to the inflammation or infection of the ethmoid sinuses. The ethmoid sinuses are a pair of small, air-filled cavities located in the upper part of the nasal cavity, near the eyes. They are surrounded by delicate bone structures and are connected to the nasal cavity by narrow channels.

Ethmoid sinusitis can occur as a result of a viral, bacterial, or fungal infection, or it may be caused by allergies, environmental factors, or structural abnormalities in the nasal passages. When the ethmoid sinuses become inflamed or infected, they can cause symptoms such as:

* Nasal congestion or stuffiness
* Pain or pressure in the forehead, between the eyes, or in the cheeks
* Headaches or facial pain
* Thick, discolored nasal discharge
* Postnasal drip
* Coughing or sneezing
* Fever
* Fatigue

Ethmoid sinusitis can be acute (lasting for a short period of time) or chronic (persisting for several weeks or months). If left untreated, ethmoid sinusitis can lead to complications such as the spread of infection to other parts of the body, including the eyes and brain. Treatment for ethmoid sinusitis may include antibiotics, decongestants, nasal sprays, or surgery in severe cases.

Gonioscopy is a diagnostic procedure in ophthalmology used to examine the anterior chamber angle, which is the area where the iris and cornea meet. This examination helps to evaluate the drainage pathways of the eye for conditions such as glaucoma. A special contact lens called a goniolens is placed on the cornea during the procedure to allow the healthcare provider to visualize the angle using a biomicroscope. The lens may be coupled with a mirrored or prismatic surface to enhance the view of the angle. Gonioscopy can help detect conditions like narrow angles, closed angles, neovascularization, and other abnormalities that might contribute to glaucoma development or progression.

The superior colliculi are a pair of prominent eminences located on the dorsal surface of the midbrain, forming part of the tectum or roof of the midbrain. They play a crucial role in the integration and coordination of visual, auditory, and somatosensory information for the purpose of directing spatial attention and ocular movements. Essentially, they are involved in the reflexive orienting of the head and eyes towards novel or significant stimuli in the environment.

In a more detailed medical definition, the superior colliculi are two rounded, convex mounds of gray matter that are situated on the roof of the midbrain, specifically at the level of the rostral mesencephalic tegmentum. Each superior colliculus has a stratified laminated structure, consisting of several layers that process different types of sensory information and control specific motor outputs.

The superficial layers of the superior colliculi primarily receive and process visual input from the retina, lateral geniculate nucleus, and other visual areas in the brain. These layers are responsible for generating spatial maps of the visual field, which allow for the localization and identification of visual stimuli.

The intermediate and deep layers of the superior colliculi receive and process auditory and somatosensory information from various sources, including the inferior colliculus, medial geniculate nucleus, and ventral posterior nucleus of the thalamus. These layers are involved in the localization and identification of auditory and tactile stimuli, as well as the coordination of head and eye movements towards these stimuli.

The superior colliculi also contain a population of neurons called "motor command neurons" that directly control the muscles responsible for orienting the eyes, head, and body towards novel or significant sensory events. These motor command neurons are activated in response to specific patterns of activity in the sensory layers of the superior colliculus, allowing for the rapid and automatic orientation of attention and gaze towards salient stimuli.

In summary, the superior colliculi are a pair of structures located on the dorsal surface of the midbrain that play a critical role in the integration and coordination of visual, auditory, and somatosensory information for the purpose of orienting attention and gaze towards salient stimuli. They contain sensory layers that generate spatial maps of the environment, as well as motor command neurons that directly control the muscles responsible for orienting the eyes, head, and body.

Paraneoplastic syndromes are a group of rare disorders that occur in some individuals with cancer. These syndromes are caused by substances produced by the tumor or the body's immune response to the tumor, which can affect distant organs and cause various symptoms.

Ocular paraneoplastic syndromes refer to a subset of these disorders that specifically affect the eyes. They are caused by an abnormal immune response directed against antigens shared by both the tumor and the nervous tissue of the eye. This results in damage to the nerve cells and can lead to various visual symptoms, such as:

1. Visual loss or blurring
2. Double vision (diplopia)
3. Light sensitivity (photophobia)
4. Abnormalities in pupil size or reactivity
5. Jerky eye movements (nystagmus)
6. Loss of peripheral vision (visual field defects)
7. Impaired color vision
8. Deterioration of the optic nerve (optic neuropathy)

Some examples of ocular paraneoplastic syndromes include:

1. Paraneoplastic retinopathy: A condition characterized by damage to the light-sensitive cells in the retina, leading to visual loss and other visual disturbances.
2. Paraneoplastic optic neuropathy: Damage to the optic nerve that can result in visual loss and visual field defects.
3. Cancer-associated retinopathy (CAR): A condition characterized by progressive vision loss, night blindness, and abnormalities in the electroretinogram (ERG), a test used to assess retinal function.
4. Melanoma-associated retinopathy (MAR): Similar to CAR but specifically associated with melanoma, this condition can cause visual loss, night blindness, and abnormal ERG results.
5. Opsoclonus-myoclonus syndrome: A rare disorder characterized by rapid, involuntary eye movements (opsoclonus) and muscle jerks (myoclonus), which can be associated with various types of cancer, including breast, lung, and ovarian cancer.

It is important to note that these conditions are relatively rare but can significantly impact a patient's quality of life. Early diagnosis and treatment of the underlying cancer can help improve outcomes for patients with ocular paraneoplastic syndromes.

Pipicolic acid is not a term that refers to a specific medical condition or disease. Instead, it is a metabolite that is involved in the body's metabolic processes.

Pipicolic acid is a type of organic compound called a cyclic amino acid, which is derived from the amino acid lysine. It is produced in the liver and is excreted in urine. Pipicolic acid has been found to have various functions in the body, including regulating the metabolism of lipids and bile acids.

Abnormal levels of pipicolic acid in the body may be associated with certain medical conditions, such as liver disease or genetic disorders that affect amino acid metabolism. However, pipicolic acid is not typically used as a diagnostic marker for these conditions.

In summary, pipicolic acid is a cyclic amino acid produced in the liver and involved in various metabolic processes in the body. Abnormal levels of pipicolic acid may be associated with certain medical conditions but are not typically used as diagnostic markers.

Neurofilament proteins (NFs) are type IV intermediate filament proteins that are specific to neurons. They are the major structural components of the neuronal cytoskeleton and play crucial roles in maintaining the structural integrity, stability, and diameter of axons. Neurofilaments are composed of three subunits: light (NFL), medium (NFM), and heavy (NFH) neurofilament proteins, which differ in their molecular weights. These subunits assemble into heteropolymers to form the neurofilament core, while the C-terminal tails of NFH and NFM extend outward from the core, interacting with other cellular components and participating in various neuronal functions. Increased levels of neurofilament proteins, particularly NFL, in cerebrospinal fluid (CSF) and blood are considered biomarkers for axonal damage and neurodegeneration in several neurological disorders, such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS).

I'm sorry for any confusion, but "mitochondrial turnover" is not a widely recognized or established medical term with a specific definition. Mitochondria are the powerhouses of the cell, responsible for producing energy in the form of ATP through a process called oxidative phosphorylation.

The term "turnover," when used in a biological context, generally refers to the process by which cells replace or regenerate their components over time. Therefore, one might infer that "mitochondrial turnover" could refer to the replacement and regeneration of mitochondria within cells. However, this is not a standardized term, and its precise meaning could vary depending on the context.

Mitochondria are known to undergo dynamic processes such as fusion (combining) and fission (dividing), which allow them to change their size, shape, and distribution in response to cellular needs. Additionally, damaged or dysfunctional mitochondria can be removed through a process called mitophagy, where they're targeted for degradation within lysosomes. New, healthy mitochondria are generated through biogenesis, which involves the production of new mitochondrial proteins and membranes.

In summary, while "mitochondrial turnover" is not a standard medical term, it could be used to describe the ongoing processes of mitochondrial dynamics, mitophagy, and biogenesis that contribute to the replacement and regeneration of mitochondria within cells over time.

Stilbamidines are a class of chemical compounds that are primarily used as veterinary medicines, specifically as parasiticides for the treatment and prevention of ectoparasites such as ticks and lice in livestock animals. Stilbamidines belong to the family of chemicals known as formamidines, which are known to have insecticidal and acaricidal properties.

The most common stilbamidine compound is chlorphentermine, which has been used as an appetite suppressant in human medicine. However, its use as a weight loss drug was discontinued due to its addictive properties and potential for serious side effects.

It's important to note that Stilbamidines are not approved for use in humans and should only be used under the supervision of a veterinarian for the intended purpose of treating and preventing ectoparasites in animals.

Acetamides are organic compounds that contain an acetamide functional group, which is a combination of an acetyl group (-COCH3) and an amide functional group (-CONH2). The general structure of an acetamide is R-CO-NH-CH3, where R represents the rest of the molecule.

Acetamides are found in various medications, including some pain relievers, muscle relaxants, and anticonvulsants. They can also be found in certain industrial chemicals and are used as intermediates in the synthesis of other organic compounds.

It is important to note that exposure to high levels of acetamides can be harmful and may cause symptoms such as headache, dizziness, nausea, and vomiting. Chronic exposure has been linked to more serious health effects, including liver and kidney damage. Therefore, handling and use of acetamides should be done with appropriate safety precautions.

Rotenone is not strictly a medical term, but it is a pesticide that is used in some medical situations. According to the National Pesticide Information Center, rotenone is a pesticide derived from the roots and stems of several plants, including Derris Eliptica, Lonchocarpus utilis, and Tephrosia vogelii. It is used as a pesticide to control insects, mites, and fish in both agricultural and residential settings.

In medical contexts, rotenone has been studied for its potential effects on human health, particularly in relation to Parkinson's disease. Some research suggests that exposure to rotenone may increase the risk of developing Parkinson's disease, although more studies are needed to confirm this link. Rotenone works by inhibiting the mitochondria in cells, which can lead to cell death and neurodegeneration.

It is important to note that rotenone is highly toxic and should be handled with care. It can cause skin and eye irritation, respiratory problems, and gastrointestinal symptoms if ingested or inhaled. Therefore, it is recommended to use personal protective equipment when handling rotenone and to follow all label instructions carefully.

Paresthesia is a medical term that describes an abnormal sensation such as tingling, numbness, prickling, or burning, usually in the hands, feet, arms, or legs. These sensations can occur without any obvious cause, often described as "pins and needles" or falling asleep in a limb. However, persistent paresthesia can be a sign of an underlying medical condition, such as nerve damage, diabetes, multiple sclerosis, or a vitamin deficiency. It is important to consult with a healthcare professional if experiencing persistent paresthesia to determine the cause and appropriate treatment.

Peroneal neuropathies refer to conditions that cause damage or dysfunction to the peroneal nerve, which is a branch of the sciatic nerve. The peroneal nerve runs down the back of the leg and wraps around the fibula bone (the smaller of the two bones in the lower leg) before dividing into two branches that innervate the muscles and skin on the front and side of the lower leg and foot.

Peroneal neuropathies can cause various symptoms, including weakness or paralysis of the ankle and toe muscles, numbness or tingling in the top of the foot and along the outside of the lower leg, and difficulty lifting the foot (known as "foot drop"). These conditions can result from trauma, compression, diabetes, or other underlying medical conditions. Treatment for peroneal neuropathies may include physical therapy, bracing, medications to manage pain, and in some cases, surgery.

Ocular vision refers to the ability to process and interpret visual information that is received by the eyes. This includes the ability to see clearly and make sense of the shapes, colors, and movements of objects in the environment. The ocular system, which includes the eye and related structures such as the optic nerve and visual cortex of the brain, works together to enable vision.

There are several components of ocular vision, including:

* Visual acuity: the clarity or sharpness of vision
* Field of vision: the extent of the visual world that is visible at any given moment
* Color vision: the ability to distinguish different colors
* Depth perception: the ability to judge the distance of objects in three-dimensional space
* Contrast sensitivity: the ability to distinguish an object from its background based on differences in contrast

Disorders of ocular vision can include refractive errors such as nearsightedness or farsightedness, as well as more serious conditions such as cataracts, glaucoma, and macular degeneration. These conditions can affect one or more aspects of ocular vision and may require medical treatment to prevent further vision loss.

Oxazolidinones are a class of synthetic antibiotics that work by inhibiting bacterial protein synthesis. They bind to the 23S ribosomal RNA of the 50S subunit, preventing the formation of the initiation complex and thus inhibiting the start of protein synthesis.

The most well-known drug in this class is linezolid (Zyvox), which is used to treat serious infections caused by Gram-positive bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE).

Oxazolidinones are typically reserved for use in patients with serious infections who have failed other antibiotic treatments, due to concerns about the development of resistance and potential side effects such as myelosuppression and peripheral neuropathy.

Fiber optic technology in the medical context refers to the use of thin, flexible strands of glass or plastic fibers that are designed to transmit light and images along their length. These fibers are used to create bundles, known as fiber optic cables, which can be used for various medical applications such as:

1. Illumination: Fiber optics can be used to deliver light to hard-to-reach areas during surgical procedures or diagnostic examinations.
2. Imaging: Fiber optics can transmit images from inside the body, enabling doctors to visualize internal structures and tissues. This is commonly used in medical imaging techniques such as endoscopy, colonoscopy, and laparoscopy.
3. Sensing: Fiber optic sensors can be used to measure various physiological parameters such as temperature, pressure, and strain within the body. These sensors can provide real-time data during surgical procedures or for monitoring patients' health status.

Fiber optic technology offers several advantages over traditional medical imaging techniques, including high resolution, flexibility, small diameter, and the ability to bend around corners without significant loss of image quality. Additionally, fiber optics are non-magnetic and can be used in MRI environments without causing interference.

Sensation disorders are conditions that affect the nervous system's ability to receive and interpret sensory information from the environment. These disorders can affect any of the five senses, including sight, hearing, touch, taste, and smell. They can result in symptoms such as numbness, tingling, pain, or loss of sensation in various parts of the body.

Some common types of sensation disorders include:

1. Neuropathy: A disorder that affects the nerves, often causing numbness, tingling, or pain in the hands and feet.
2. Central pain syndrome: A condition that results from damage to the brain or spinal cord, leading to chronic pain.
3. Tinnitus: A ringing or buzzing sound in the ears that can be a symptom of an underlying hearing disorder.
4. Ageusia: The loss of taste sensation, often caused by damage to the tongue or nerves that transmit taste information to the brain.
5. Anosmia: The loss of smell sensation, which can result from a variety of causes including injury, infection, or neurological disorders.

Sensation disorders can have significant impacts on a person's quality of life and ability to perform daily activities. Treatment may involve medication, physical therapy, or other interventions aimed at addressing the underlying cause of the disorder.

Infrared rays are not typically considered in the context of medical definitions. They are a type of electromagnetic radiation with longer wavelengths than those of visible light, ranging from 700 nanometers to 1 millimeter. In the field of medicine, infrared radiation is sometimes used in therapeutic settings for its heat properties, such as in infrared saunas or infrared therapy devices. However, infrared rays themselves are not a medical condition or diagnosis.

Disease progression is the worsening or advancement of a medical condition over time. It refers to the natural course of a disease, including its development, the severity of symptoms and complications, and the impact on the patient's overall health and quality of life. Understanding disease progression is important for developing appropriate treatment plans, monitoring response to therapy, and predicting outcomes.

The rate of disease progression can vary widely depending on the type of medical condition, individual patient factors, and the effectiveness of treatment. Some diseases may progress rapidly over a short period of time, while others may progress more slowly over many years. In some cases, disease progression may be slowed or even halted with appropriate medical interventions, while in other cases, the progression may be inevitable and irreversible.

In clinical practice, healthcare providers closely monitor disease progression through regular assessments, imaging studies, and laboratory tests. This information is used to guide treatment decisions and adjust care plans as needed to optimize patient outcomes and improve quality of life.

Medical Definition:

"Risk factors" are any attribute, characteristic or exposure of an individual that increases the likelihood of developing a disease or injury. They can be divided into modifiable and non-modifiable risk factors. Modifiable risk factors are those that can be changed through lifestyle choices or medical treatment, while non-modifiable risk factors are inherent traits such as age, gender, or genetic predisposition. Examples of modifiable risk factors include smoking, alcohol consumption, physical inactivity, and unhealthy diet, while non-modifiable risk factors include age, sex, and family history. It is important to note that having a risk factor does not guarantee that a person will develop the disease, but rather indicates an increased susceptibility.

The myelin sheath is a multilayered, fatty substance that surrounds and insulates many nerve fibers in the nervous system. It is essential for the rapid transmission of electrical signals, or nerve impulses, along these nerve fibers, allowing for efficient communication between different parts of the body. The myelin sheath is produced by specialized cells called oligodendrocytes in the central nervous system (CNS) and Schwann cells in the peripheral nervous system (PNS). Damage to the myelin sheath, as seen in conditions like multiple sclerosis, can significantly impair nerve function and result in various neurological symptoms.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Prospective studies, also known as longitudinal studies, are a type of cohort study in which data is collected forward in time, following a group of individuals who share a common characteristic or exposure over a period of time. The researchers clearly define the study population and exposure of interest at the beginning of the study and follow up with the participants to determine the outcomes that develop over time. This type of study design allows for the investigation of causal relationships between exposures and outcomes, as well as the identification of risk factors and the estimation of disease incidence rates. Prospective studies are particularly useful in epidemiology and medical research when studying diseases with long latency periods or rare outcomes.

An acute disease is a medical condition that has a rapid onset, develops quickly, and tends to be short in duration. Acute diseases can range from minor illnesses such as a common cold or flu, to more severe conditions such as pneumonia, meningitis, or a heart attack. These types of diseases often have clear symptoms that are easy to identify, and they may require immediate medical attention or treatment.

Acute diseases are typically caused by an external agent or factor, such as a bacterial or viral infection, a toxin, or an injury. They can also be the result of a sudden worsening of an existing chronic condition. In general, acute diseases are distinct from chronic diseases, which are long-term medical conditions that develop slowly over time and may require ongoing management and treatment.

Examples of acute diseases include:

* Acute bronchitis: a sudden inflammation of the airways in the lungs, often caused by a viral infection.
* Appendicitis: an inflammation of the appendix that can cause severe pain and requires surgical removal.
* Gastroenteritis: an inflammation of the stomach and intestines, often caused by a viral or bacterial infection.
* Migraine headaches: intense headaches that can last for hours or days, and are often accompanied by nausea, vomiting, and sensitivity to light and sound.
* Myocardial infarction (heart attack): a sudden blockage of blood flow to the heart muscle, often caused by a buildup of plaque in the coronary arteries.
* Pneumonia: an infection of the lungs that can cause coughing, chest pain, and difficulty breathing.
* Sinusitis: an inflammation of the sinuses, often caused by a viral or bacterial infection.

It's important to note that while some acute diseases may resolve on their own with rest and supportive care, others may require medical intervention or treatment to prevent complications and promote recovery. If you are experiencing symptoms of an acute disease, it is always best to seek medical attention to ensure proper diagnosis and treatment.

Hyperbaric oxygenation is a medical treatment in which a patient breathes pure oxygen in a pressurized chamber, typically at greater than one atmosphere absolute (ATA). This process results in increased levels of oxygen being dissolved in the blood and delivered to body tissues, thereby promoting healing, reducing inflammation, and combating infection. Hyperbaric oxygen therapy is used to treat various medical conditions, including carbon monoxide poisoning, decompression sickness, gangrene, and wounds that are slow to heal due to diabetes or radiation injury.

Central hearing loss is a type of hearing disorder that occurs due to damage or dysfunction in the central auditory pathways of the brain, rather than in the ear itself. This condition can result from various causes, such as stroke, tumors, trauma, infection, or degenerative diseases affecting the brain.

In central hearing loss, the person may have difficulty understanding and processing speech, even when they can hear sounds at normal levels. They might experience problems with sound localization, discriminating between similar sounds, and comprehending complex auditory signals. This type of hearing loss is different from sensorineural or conductive hearing loss, which are related to issues in the outer, middle, or inner ear.

Color perception refers to the ability to detect, recognize, and differentiate various colors and color patterns in the visual field. This complex process involves the functioning of both the eyes and the brain.

The eye's retina contains two types of photoreceptor cells called rods and cones. Rods are more sensitive to light and dark changes and help us see in low-light conditions, but they do not contribute much to color vision. Cones, on the other hand, are responsible for color perception and function best in well-lit conditions.

There are three types of cone cells, each sensitive to a particular range of wavelengths corresponding to blue, green, and red colors. The combination of signals from these three types of cones allows us to perceive a wide spectrum of colors.

The brain then interprets these signals and translates them into the perception of different colors and hues. It is important to note that color perception can be influenced by various factors, including cultural background, personal experiences, and even language. Some individuals may also have deficiencies in color perception due to genetic or acquired conditions, such as color blindness or cataracts.

"Rats, Inbred BN" are a strain of laboratory rats (Rattus norvegicus) that have been inbred for many generations to maintain a high level of genetic consistency and uniformity within the strain. The "BN" designation refers to the place where they were first developed, Bratislava, Czechoslovakia (now Slovakia).

These rats are often used in biomedical research because their genetic homogeneity makes them useful for studying the effects of specific genes or environmental factors on health and disease. They have been widely used as a model organism to study various physiological and pathophysiological processes, including hypertension, kidney function, immunology, and neuroscience.

Inbred BN rats are known for their low renin-angiotensin system activity, which makes them a useful model for studying hypertension and related disorders. They also have a unique sensitivity to dietary protein, making them a valuable tool for studying the relationship between diet and kidney function.

Overall, Inbred BN rats are an important tool in biomedical research, providing researchers with a consistent and well-characterized model organism for studying various aspects of human health and disease.

A heterozygote is an individual who has inherited two different alleles (versions) of a particular gene, one from each parent. This means that the individual's genotype for that gene contains both a dominant and a recessive allele. The dominant allele will be expressed phenotypically (outwardly visible), while the recessive allele may or may not have any effect on the individual's observable traits, depending on the specific gene and its function. Heterozygotes are often represented as 'Aa', where 'A' is the dominant allele and 'a' is the recessive allele.

A phenotype is the physical or biochemical expression of an organism's genes, or the observable traits and characteristics resulting from the interaction of its genetic constitution (genotype) with environmental factors. These characteristics can include appearance, development, behavior, and resistance to disease, among others. Phenotypes can vary widely, even among individuals with identical genotypes, due to differences in environmental influences, gene expression, and genetic interactions.

A closed head injury is a type of traumatic brain injury (TBI) that occurs when there is no penetration or breakage of the skull. The brain is encased in the skull and protected by cerebrospinal fluid, but when the head experiences a sudden impact or jolt, the brain can move back and forth within the skull, causing it to bruise, tear blood vessels, or even cause nerve damage. This type of injury can result from various incidents such as car accidents, sports injuries, falls, or any other event that causes the head to suddenly stop or change direction quickly.

Closed head injuries can range from mild (concussion) to severe (diffuse axonal injury, epidural hematoma, subdural hematoma), and symptoms may not always be immediately apparent. They can include headache, dizziness, nausea, vomiting, confusion, memory loss, difficulty concentrating, mood changes, sleep disturbances, and in severe cases, loss of consciousness, seizures, or even coma. It is essential to seek medical attention immediately if you suspect a closed head injury, as prompt diagnosis and treatment can significantly improve the outcome.

The oculomotor muscles are a group of extraocular muscles that control the movements of the eye. They include:

1. Superior rectus: This muscle is responsible for elevating the eye and helping with inward rotation (intorsion) when looking downwards.
2. Inferior rectus: It depresses the eye and helps with outward rotation (extorsion) when looking upwards.
3. Medial rectus: This muscle adducts, or moves, the eye towards the midline of the face.
4. Inferior oblique: The inferior oblique muscle intorts and elevates the eye.
5. Superior oblique: It extorts and depresses the eye.

These muscles work together to allow for smooth and precise movements of the eyes, enabling tasks such as tracking moving objects, reading, and maintaining visual fixation on a single point in space.

"Cell count" is a medical term that refers to the process of determining the number of cells present in a given volume or sample of fluid or tissue. This can be done through various laboratory methods, such as counting individual cells under a microscope using a specialized grid called a hemocytometer, or using automated cell counters that use light scattering and electrical impedance techniques to count and classify different types of cells.

Cell counts are used in a variety of medical contexts, including hematology (the study of blood and blood-forming tissues), microbiology (the study of microscopic organisms), and pathology (the study of diseases and their causes). For example, a complete blood count (CBC) is a routine laboratory test that includes a white blood cell (WBC) count, red blood cell (RBC) count, hemoglobin level, hematocrit value, and platelet count. Abnormal cell counts can indicate the presence of various medical conditions, such as infections, anemia, or leukemia.

The Ulnar nerve is one of the major nerves in the forearm and hand, which provides motor function to the majority of the intrinsic muscles of the hand (except for those innervated by the median nerve) and sensory innervation to the little finger and half of the ring finger. It originates from the brachial plexus, passes through the cubital tunnel at the elbow, and continues down the forearm, where it runs close to the ulna bone. The ulnar nerve then passes through the Guyon's canal in the wrist before branching out to innervate the hand muscles and provide sensation to the skin on the little finger and half of the ring finger.

Oxidative phosphorylation is the metabolic process by which cells use enzymes to generate energy in the form of adenosine triphosphate (ATP) from the oxidation of nutrients, such as glucose or fatty acids. This process occurs in the inner mitochondrial membrane of eukaryotic cells and is facilitated by the electron transport chain, which consists of a series of protein complexes that transfer electrons from donor molecules to acceptor molecules. As the electrons are passed along the chain, they release energy that is used to pump protons across the membrane, creating a gradient. The ATP synthase enzyme then uses the flow of protons back across the membrane to generate ATP, which serves as the main energy currency for cellular processes.

Monocular vision refers to the ability to see and process visual information using only one eye. It is the type of vision that an individual has when they are using only one eye to look at something, while the other eye may be covered or not functioning. This can be contrasted with binocular vision, which involves the use of both eyes working together to provide depth perception and a single, combined visual field.

Monocular vision is important for tasks that only require the use of one eye, such as when looking through a microscope or using a telescope. However, it does not provide the same level of depth perception and spatial awareness as binocular vision. In some cases, individuals may have reduced visual acuity or other visual impairments in one eye, leading to limited monocular vision in that eye. It is important for individuals with monocular vision to have regular eye exams to monitor their eye health and ensure that any visual impairments are detected and treated promptly.

Astrocytes are a type of star-shaped glial cell found in the central nervous system (CNS), including the brain and spinal cord. They play crucial roles in supporting and maintaining the health and function of neurons, which are the primary cells responsible for transmitting information in the CNS.

Some of the essential functions of astrocytes include:

1. Supporting neuronal structure and function: Astrocytes provide structural support to neurons by ensheathing them and maintaining the integrity of the blood-brain barrier, which helps regulate the entry and exit of substances into the CNS.
2. Regulating neurotransmitter levels: Astrocytes help control the levels of neurotransmitters in the synaptic cleft (the space between two neurons) by taking up excess neurotransmitters and breaking them down, thus preventing excessive or prolonged activation of neuronal receptors.
3. Providing nutrients to neurons: Astrocytes help supply energy metabolites, such as lactate, to neurons, which are essential for their survival and function.
4. Modulating synaptic activity: Through the release of various signaling molecules, astrocytes can modulate synaptic strength and plasticity, contributing to learning and memory processes.
5. Participating in immune responses: Astrocytes can respond to CNS injuries or infections by releasing pro-inflammatory cytokines and chemokines, which help recruit immune cells to the site of injury or infection.
6. Promoting neuronal survival and repair: In response to injury or disease, astrocytes can become reactive and undergo morphological changes that aid in forming a glial scar, which helps contain damage and promote tissue repair. Additionally, they release growth factors and other molecules that support the survival and regeneration of injured neurons.

Dysfunction or damage to astrocytes has been implicated in several neurological disorders, including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS).

Motor Neuron Disease (MND) is a progressive neurodegenerative disorder that affects the motor neurons, which are nerve cells in the brain and spinal cord responsible for controlling voluntary muscles involved in movement, speaking, breathing, and swallowing. As the motor neurons degenerate and die, they stop sending signals to the muscles, causing them to weaken, waste away (atrophy), and eventually lead to paralysis.

There are several types of MND, including:

1. Amyotrophic Lateral Sclerosis (ALS): Also known as Lou Gehrig's disease, this is the most common form of MND. It affects both upper and lower motor neurons, causing muscle weakness, stiffness, twitching, and atrophy throughout the body.
2. Progressive Bulbar Palsy (PBP): This type primarily affects the bulbar muscles in the brainstem, which control speech, swallowing, and chewing. Patients with PBP experience difficulties with speaking, slurred speech, and problems swallowing and may also have weak facial muscles and limb weakness.
3. Primary Lateral Sclerosis (PLS): This form of MND affects only the upper motor neurons, causing muscle stiffness, spasticity, and weakness, primarily in the legs. PLS progresses more slowly than ALS, and patients usually maintain their ability to speak and swallow for a longer period.
4. Progressive Muscular Atrophy (PMA): This type of MND affects only the lower motor neurons, causing muscle wasting, weakness, and fasciculations (muscle twitches). PMA progresses more slowly than ALS but can still be severely disabling over time.
5. Spinal Muscular Atrophy (SMA): This is a genetic form of MND that typically presents in infancy or childhood, although adult-onset forms exist. SMA affects the lower motor neurons in the spinal cord, causing muscle weakness and atrophy, primarily in the legs and trunk.

The exact cause of Motor Neuron Disease is not fully understood, but it is believed to involve a combination of genetic, environmental, and lifestyle factors. There is currently no cure for MND, and treatment focuses on managing symptoms, maintaining quality of life, and slowing disease progression through various therapies and medications.

Glial Fibrillary Acidic Protein (GFAP) is a type of intermediate filament protein that is primarily found in astrocytes, which are a type of star-shaped glial cells in the central nervous system (CNS). These proteins play an essential role in maintaining the structural integrity and stability of astrocytes. They also participate in various cellular processes such as responding to injury, providing support to neurons, and regulating the extracellular environment.

GFAP is often used as a marker for astrocytic activation or reactivity, which can occur in response to CNS injuries, neuroinflammation, or neurodegenerative diseases. Elevated GFAP levels in cerebrospinal fluid (CSF) or blood can indicate astrocyte damage or dysfunction and are associated with several neurological conditions, including traumatic brain injury, stroke, multiple sclerosis, Alzheimer's disease, and Alexander's disease.

The Fluorescent Antibody Technique (FAT), Indirect is a type of immunofluorescence assay used to detect the presence of specific antigens in a sample. In this method, the sample is first incubated with a primary antibody that binds to the target antigen. After washing to remove unbound primary antibodies, a secondary fluorescently labeled antibody is added, which recognizes and binds to the primary antibody. This indirect labeling approach allows for amplification of the signal, making it more sensitive than direct methods. The sample is then examined under a fluorescence microscope to visualize the location and amount of antigen based on the emitted light from the fluorescent secondary antibody. It's commonly used in diagnostic laboratories for detection of various bacteria, viruses, and other antigens in clinical specimens.

Cat-scratch disease (CSD) is a bacterial infection caused by Bartonella henselae. It is typically transmitted through contact with a cat, especially when the animal scratches or bites a person and then introduces the bacteria into the wound. The incubation period for CSD is usually 7-14 days after exposure.

The most common symptoms of CSD include:

* A small, raised bump (called a papule) that develops at the site of the scratch or bite within a few days of being scratched or bitten by a cat. This bump may be tender and can sometimes form a crust or pustule.
* Swollen lymph nodes (also called lymphadenopathy) near the site of the infection, which usually develop 1-2 weeks after the initial scratch or bite. These swollen lymph nodes are often painful and may be warm to the touch.
* Fatigue, fever, headache, and muscle aches are also common symptoms of CSD.

In most cases, cat-scratch disease is a mild illness that resolves on its own within a few weeks or months. However, in some cases, it can cause more severe complications, such as infection of the heart valves (endocarditis), inflammation of the brain (encephalitis), or damage to the eyes (retinitis).

Treatment for cat-scratch disease typically involves supportive care, such as pain relief and anti-inflammatory medications. Antibiotics may be prescribed in some cases, particularly if the infection is severe or if the patient has a weakened immune system. Preventive measures include washing hands after handling cats, avoiding rough play with cats, and promptly treating cat bites and scratches.

Heterozygote detection is a method used in genetics to identify individuals who carry one normal and one mutated copy of a gene. These individuals are known as heterozygotes and they do not typically show symptoms of the genetic disorder associated with the mutation, but they can pass the mutated gene on to their offspring, who may then be affected.

Heterozygote detection is often used in genetic counseling and screening programs for recessive disorders such as cystic fibrosis or sickle cell anemia. By identifying heterozygotes, individuals can be informed of their carrier status and the potential risks to their offspring. This information can help them make informed decisions about family planning and reproductive options.

Various methods can be used for heterozygote detection, including polymerase chain reaction (PCR) based tests, DNA sequencing, and genetic linkage analysis. The choice of method depends on the specific gene or mutation being tested, as well as the availability and cost of the testing technology.

Radiation injuries refer to the damages that occur to living tissues as a result of exposure to ionizing radiation. These injuries can be acute, occurring soon after exposure to high levels of radiation, or chronic, developing over a longer period after exposure to lower levels of radiation. The severity and type of injury depend on the dose and duration of exposure, as well as the specific tissues affected.

Acute radiation syndrome (ARS), also known as radiation sickness, is the most severe form of acute radiation injury. It can cause symptoms such as nausea, vomiting, diarrhea, fatigue, fever, and skin burns. In more severe cases, it can lead to neurological damage, hemorrhage, infection, and death.

Chronic radiation injuries, on the other hand, may not appear until months or even years after exposure. They can cause a range of symptoms, including fatigue, weakness, skin changes, cataracts, reduced fertility, and an increased risk of cancer.

Radiation injuries can be treated with supportive care, such as fluids and electrolytes replacement, antibiotics, wound care, and blood transfusions. In some cases, surgery may be necessary to remove damaged tissue or control bleeding. Prevention is the best approach to radiation injuries, which includes limiting exposure through proper protective measures and monitoring radiation levels in the environment.

Polyradiculoneuropathy is a medical term that refers to a condition affecting multiple nerve roots and peripheral nerves. It's a type of neuropathy, which is damage or disease affecting the peripheral nerves, and it involves damage to the nerve roots as they exit the spinal cord.

The term "poly" means many, "radiculo" refers to the nerve root, and "neuropathy" indicates a disorder of the nerves. Therefore, polyradiculoneuropathy implies that multiple nerve roots and peripheral nerves are affected.

This condition can result from various causes, such as infections (like Guillain-Barre syndrome), autoimmune disorders (such as lupus or rheumatoid arthritis), diabetes, cancer, or exposure to toxins. Symptoms may include weakness, numbness, tingling, or pain in the limbs, which can progress and become severe over time. Proper diagnosis and management are crucial for improving outcomes and preventing further nerve damage.

Eye proteins, also known as ocular proteins, are specific proteins that are found within the eye and play crucial roles in maintaining proper eye function and health. These proteins can be found in various parts of the eye, including the cornea, iris, lens, retina, and other structures. They perform a wide range of functions, such as:

1. Structural support: Proteins like collagen and elastin provide strength and flexibility to the eye's tissues, enabling them to maintain their shape and withstand mechanical stress.
2. Light absorption and transmission: Proteins like opsins and crystallins are involved in capturing and transmitting light signals within the eye, which is essential for vision.
3. Protection against damage: Some eye proteins, such as antioxidant enzymes and heat shock proteins, help protect the eye from oxidative stress, UV radiation, and other environmental factors that can cause damage.
4. Regulation of eye growth and development: Various growth factors and signaling molecules, which are protein-based, contribute to the proper growth, differentiation, and maintenance of eye tissues during embryonic development and throughout adulthood.
5. Immune defense: Proteins involved in the immune response, such as complement components and immunoglobulins, help protect the eye from infection and inflammation.
6. Maintenance of transparency: Crystallin proteins in the lens maintain its transparency, allowing light to pass through unobstructed for clear vision.
7. Neuroprotection: Certain eye proteins, like brain-derived neurotrophic factor (BDNF), support the survival and function of neurons within the retina, helping to preserve vision.

Dysfunction or damage to these eye proteins can contribute to various eye disorders and diseases, such as cataracts, age-related macular degeneration, glaucoma, diabetic retinopathy, and others.

Familial amyloid neuropathies are a group of inherited disorders characterized by the accumulation of abnormal deposits of amyloid proteins in various tissues and organs of the body. These abnormal deposits can cause damage to nerves, leading to a peripheral neuropathy that affects sensation, movement, and organ function.

There are several types of familial amyloid neuropathies, each caused by different genetic mutations. The most common type is known as transthyretin-related hereditary amyloidosis (TTR-HA), which is caused by mutations in the TTR gene. Other types include apolipoprotein A1-related hereditary amyloidosis (APOA1-HA) and gelsolin-related amyloidosis (AGel-HA).

Symptoms of familial amyloid neuropathies can vary depending on the type and severity of the disorder. Common symptoms include:

* Numbness, tingling, or pain in the hands and feet
* Weakness or loss of muscle strength in the legs and arms
* Autonomic nervous system dysfunction, leading to problems with digestion, heart rate, blood pressure, and temperature regulation
* Carpal tunnel syndrome
* Eye abnormalities, such as vitreous opacities or retinal deposits
* Kidney disease

Familial amyloid neuropathies are typically inherited in an autosomal dominant manner, meaning that a child has a 50% chance of inheriting the mutated gene from an affected parent. Diagnosis is usually made through genetic testing and confirmation of the presence of amyloid deposits in tissue samples.

Treatment for familial amyloid neuropathies typically involves managing symptoms and slowing the progression of the disease. This may include medications to control pain, physical therapy to maintain muscle strength and mobility, and devices such as braces or wheelchairs to assist with mobility. In some cases, liver transplantation may be recommended to remove the source of the mutated transthyretin protein.

A coloboma is a congenital condition that results from incomplete closure of the optic fissure during fetal development. This results in a gap or hole in one or more structures of the eye, such as the iris, retina, choroid, or optic nerve. The size and location of the coloboma can vary widely, and it may affect one or both eyes.

Colobomas can cause a range of visual symptoms, depending on their size and location. Some people with colobomas may have no visual impairment, while others may experience reduced vision, double vision, or sensitivity to light. In severe cases, colobomas can lead to blindness.

Colobomas are usually diagnosed during routine eye exams and are typically not treatable, although some visual symptoms may be managed with glasses, contact lenses, or surgery in certain cases. Colobomas can occur as an isolated condition or as part of a genetic syndrome, so individuals with colobomas may benefit from genetic counseling to understand their risk of passing the condition on to their offspring.

A missense mutation is a type of point mutation in which a single nucleotide change results in the substitution of a different amino acid in the protein that is encoded by the affected gene. This occurs when the altered codon (a sequence of three nucleotides that corresponds to a specific amino acid) specifies a different amino acid than the original one. The function and/or stability of the resulting protein may be affected, depending on the type and location of the missense mutation. Missense mutations can have various effects, ranging from benign to severe, depending on the importance of the changed amino acid for the protein's structure or function.

Myelin P0 protein, also known as P0 or MPZ (myelin protein zero), is a major structural component of the myelin sheath in the peripheral nervous system. The myelin sheath is a multilayered membrane that surrounds and insulates nerve fibers to increase the speed of electrical impulse transmission.

P0 protein is a transmembrane glycoprotein, which means it spans the lipid bilayer of the myelin membrane and has sugar molecules (glycans) attached to it. It plays a crucial role in maintaining the compact structure of the myelin sheath by forming homodimers that interact with each other through their extracellular domains, creating tight junctions between the apposing layers of the myelin membrane.

P0 protein also contributes to the stability and integrity of the myelin sheath by interacting with other myelin proteins, such as connexin 32 and peripheral myelin protein 22 (PMP22). Mutations in the MPZ gene can lead to various peripheral neuropathies, including Charcot-Marie-Tooth disease type 1B and Dejerine-Sottas syndrome.

Atrophy is a medical term that refers to the decrease in size and wasting of an organ or tissue due to the disappearance of cells, shrinkage of cells, or decreased number of cells. This process can be caused by various factors such as disuse, aging, degeneration, injury, or disease.

For example, if a muscle is immobilized for an extended period, it may undergo atrophy due to lack of use. Similarly, certain medical conditions like diabetes, cancer, and heart failure can lead to the wasting away of various tissues and organs in the body.

Atrophy can also occur as a result of natural aging processes, leading to decreased muscle mass and strength in older adults. In general, atrophy is characterized by a decrease in the volume or weight of an organ or tissue, which can have significant impacts on its function and overall health.

Tibial neuropathy refers to damage or dysfunction of the tibial nerve, which is one of the major nerves in the leg. The tibial nerve provides motor and sensory innervation to the lower leg, ankle, and foot muscles, as well as the skin on the sole of the foot.

Tibial neuropathy can result from various causes, including trauma, compression, diabetes, or other systemic diseases that affect the nerves. The symptoms of tibial neuropathy may include pain, numbness, tingling, or weakness in the affected leg and foot. In severe cases, it can lead to muscle wasting and difficulty walking.

The diagnosis of tibial neuropathy typically involves a thorough physical examination, including a neurological assessment, as well as electrical testing of nerve function (nerve conduction studies and electromyography). Treatment depends on the underlying cause but may include medication, physical therapy, or surgery in some cases.

Paraneoplastic polyneuropathy is a rare neurological disorder that can occur in some individuals with cancer. It's caused by the immune system producing antibodies or cells that attack the nervous system (neurons, nerve axons, or myelin sheath) as a response to the presence of a tumor or cancer in the body.

The term "polyneuropathy" refers to damage or dysfunction affecting multiple peripheral nerves simultaneously. This can lead to various symptoms such as numbness, tingling, muscle weakness, and pain, typically starting in the hands and feet and progressing upwards.

In paraneoplastic polyneuropathy, these symptoms are related to the immune system's response to the cancer rather than direct invasion of the nerves by the tumor itself. The specific type of polyneuropathy can vary between individuals, and it may present as sensorimotor polyneuropathy, autonomic neuropathy, or a combination of both.

Early diagnosis and treatment of the underlying cancer are crucial for managing paraneoplastic polyneuropathy. Immunotherapy, plasma exchange, and intravenous immunoglobulin may be used to help control the immune response and alleviate symptoms.

A neurological examination is a series of tests used to evaluate the functioning of the nervous system, including both the central nervous system (the brain and spinal cord) and peripheral nervous system (the nerves that extend from the brain and spinal cord to the rest of the body). It is typically performed by a healthcare professional such as a neurologist or a primary care physician with specialized training in neurology.

During a neurological examination, the healthcare provider will assess various aspects of neurological function, including:

1. Mental status: This involves evaluating a person's level of consciousness, orientation, memory, and cognitive abilities.
2. Cranial nerves: There are 12 cranial nerves that control functions such as vision, hearing, smell, taste, and movement of the face and neck. The healthcare provider will test each of these nerves to ensure they are functioning properly.
3. Motor function: This involves assessing muscle strength, tone, coordination, and reflexes. The healthcare provider may ask the person to perform certain movements or tasks to evaluate these functions.
4. Sensory function: The healthcare provider will test a person's ability to feel different types of sensations, such as touch, pain, temperature, vibration, and proprioception (the sense of where your body is in space).
5. Coordination and balance: The healthcare provider may assess a person's ability to perform coordinated movements, such as touching their finger to their nose or walking heel-to-toe.
6. Reflexes: The healthcare provider will test various reflexes throughout the body using a reflex hammer.

The results of a neurological examination can help healthcare providers diagnose and monitor conditions that affect the nervous system, such as stroke, multiple sclerosis, Parkinson's disease, or peripheral neuropathy.

Rhodopsin, also known as visual purple, is a light-sensitive protein found in the rods of the eye's retina. It is a type of opsin, a class of proteins that are activated by light and play a crucial role in vision. Rhodopsin is composed of two parts: an apoprotein called opsin and a chromophore called 11-cis-retinal. When light hits the retina, it changes the shape of the 11-cis-retinal, which in turn activates the rhodopsin protein. This activation triggers a series of chemical reactions that ultimately lead to the transmission of a visual signal to the brain. Rhodopsin is highly sensitive to light and allows for vision in low-light conditions.

Neuralgia is a type of pain that occurs along the pathway of a nerve, often caused by damage or irritation to the nerve. It is typically described as a sharp, stabbing, burning, or electric-shock like pain that can be severe and debilitating. Neuralgia can affect any nerve in the body, but it most commonly occurs in the facial area (trigeminal neuralgia) or in the nerves related to the spine (postherpetic neuralgia). The pain associated with neuralgia can be intermittent or constant and may be worsened by certain triggers such as touch, temperature changes, or movement. Treatment for neuralgia typically involves medications to manage pain, as well as other therapies such as nerve blocks, surgery, or lifestyle modifications.

The vestibulocochlear nerve, also known as the 8th cranial nerve, is responsible for transmitting sound and balance information from the inner ear to the brain. Vestibulocochlear nerve diseases refer to conditions that affect this nerve and can result in hearing loss, vertigo, and balance problems.

These diseases can be caused by various factors, including genetics, infection, trauma, tumors, or degeneration. Some examples of vestibulocochlear nerve diseases include:

1. Vestibular neuritis: an inner ear infection that causes severe vertigo, nausea, and balance problems.
2. Labyrinthitis: an inner ear infection that affects both the vestibular and cochlear nerves, causing vertigo, hearing loss, and tinnitus.
3. Acoustic neuroma: a benign tumor that grows on the vestibulocochlear nerve, causing hearing loss, tinnitus, and balance problems.
4. Meniere's disease: a inner ear disorder that causes vertigo, hearing loss, tinnitus, and a feeling of fullness in the ear.
5. Ototoxicity: damage to the inner ear caused by certain medications or chemicals that can result in hearing loss and balance problems.
6. Vestibular migraine: a type of migraine that is associated with vertigo, dizziness, and balance problems.

Treatment for vestibulocochlear nerve diseases varies depending on the specific condition and its severity. It may include medication, physical therapy, surgery, or a combination of these approaches.

Glucocorticoids are a class of steroid hormones that are naturally produced in the adrenal gland, or can be synthetically manufactured. They play an essential role in the metabolism of carbohydrates, proteins, and fats, and have significant anti-inflammatory effects. Glucocorticoids suppress immune responses and inflammation by inhibiting the release of inflammatory mediators from various cells, such as mast cells, eosinophils, and lymphocytes. They are frequently used in medical treatment for a wide range of conditions, including allergies, asthma, rheumatoid arthritis, dermatological disorders, and certain cancers. Prolonged use or high doses of glucocorticoids can lead to several side effects, such as weight gain, mood changes, osteoporosis, and increased susceptibility to infections.

Myelin proteins are proteins that are found in the myelin sheath, which is a fatty (lipid-rich) substance that surrounds and insulates nerve fibers (axons) in the nervous system. The myelin sheath enables the rapid transmission of electrical signals (nerve impulses) along the axons, allowing for efficient communication between different parts of the nervous system.

There are several types of myelin proteins, including:

1. Proteolipid protein (PLP): This is the most abundant protein in the myelin sheath and plays a crucial role in maintaining the structure and function of the myelin sheath.
2. Myelin basic protein (MBP): This protein is also found in the myelin sheath and helps to stabilize the compact structure of the myelin sheath.
3. Myelin-associated glycoprotein (MAG): This protein is involved in the adhesion of the myelin sheath to the axon and helps to maintain the integrity of the myelin sheath.
4. 2'3'-cyclic nucleotide 3' phosphodiesterase (CNP): This protein is found in oligodendrocytes, which are the cells that produce the myelin sheath in the central nervous system. CNP plays a role in maintaining the structure and function of the oligodendrocytes.

Damage to myelin proteins can lead to demyelination, which is a characteristic feature of several neurological disorders, including multiple sclerosis (MS), Guillain-Barré syndrome, and Charcot-Marie-Tooth disease.

Sciatic neuropathy is a condition that results from damage or injury to the sciatic nerve, which is the largest nerve in the human body. The sciatic nerve originates from the lower spine (lumbar and sacral regions) and travels down through the buttocks, hips, and legs to the feet.

Sciatic neuropathy can cause various symptoms, including pain, numbness, tingling, weakness, or difficulty moving the affected leg or foot. The pain associated with sciatic neuropathy is often described as sharp, shooting, or burning and may worsen with movement, coughing, or sneezing.

The causes of sciatic neuropathy include compression or irritation of the nerve due to conditions such as herniated discs, spinal stenosis, bone spurs, tumors, or piriformis syndrome. Trauma or injury to the lower back, hip, or buttocks can also cause sciatic neuropathy.

Diagnosing sciatic neuropathy typically involves a physical examination and medical history, as well as imaging tests such as X-rays, MRI, or CT scans to visualize the spine and surrounding structures. Treatment options may include pain management, physical therapy, steroid injections, or surgery, depending on the severity and underlying cause of the condition.

Guillain-Barré syndrome (GBS) is a rare autoimmune disorder in which the body's immune system mistakenly attacks the peripheral nervous system, leading to muscle weakness, tingling sensations, and sometimes paralysis. The peripheral nervous system includes the nerves that control our movements and transmit signals from our skin, muscles, and joints to our brain.

The onset of GBS usually occurs after a viral or bacterial infection, such as respiratory or gastrointestinal infections, or following surgery, vaccinations, or other immune system triggers. The exact cause of the immune response that leads to GBS is not fully understood.

GBS typically progresses rapidly over days or weeks, with symptoms reaching their peak within 2-4 weeks after onset. Most people with GBS experience muscle weakness that starts in the lower limbs and spreads upward to the upper body, arms, and face. In severe cases, the diaphragm and chest muscles may become weakened, leading to difficulty breathing and requiring mechanical ventilation.

The diagnosis of GBS is based on clinical symptoms, nerve conduction studies, and sometimes cerebrospinal fluid analysis. Treatment typically involves supportive care, such as pain management, physical therapy, and respiratory support if necessary. In addition, plasma exchange (plasmapheresis) or intravenous immunoglobulin (IVIG) may be used to reduce the severity of symptoms and speed up recovery.

While most people with GBS recover completely or with minimal residual symptoms, some may experience long-term disability or require ongoing medical care. The prognosis for GBS varies depending on the severity of the illness and the individual's age and overall health.

Mandibular diseases refer to conditions that affect the mandible, or lower jawbone. These diseases can be classified as congenital (present at birth) or acquired (developing after birth). They can also be categorized based on the tissues involved, such as bone, muscle, or cartilage. Some examples of mandibular diseases include:

1. Mandibular fractures: These are breaks in the lower jawbone that can result from trauma or injury.
2. Osteomyelitis: This is an infection of the bone and surrounding tissues, which can affect the mandible.
3. Temporomandibular joint (TMJ) disorders: These are conditions that affect the joint that connects the jawbone to the skull, causing pain and limited movement.
4. Mandibular tumors: These are abnormal growths that can be benign or malignant, and can develop in any of the tissues of the mandible.
5. Osteonecrosis: This is a condition where the bone tissue dies due to lack of blood supply, which can affect the mandible.
6. Cleft lip and palate: This is a congenital deformity that affects the development of the face and mouth, including the lower jawbone.
7. Mandibular hypoplasia: This is a condition where the lower jawbone does not develop properly, leading to a small or recessed chin.
8. Developmental disorders: These are conditions that affect the growth and development of the mandible, such as condylar hyperplasia or hemifacial microsomia.

Cell death is the process by which cells cease to function and eventually die. There are several ways that cells can die, but the two most well-known and well-studied forms of cell death are apoptosis and necrosis.

Apoptosis is a programmed form of cell death that occurs as a normal and necessary process in the development and maintenance of healthy tissues. During apoptosis, the cell's DNA is broken down into small fragments, the cell shrinks, and the membrane around the cell becomes fragmented, allowing the cell to be easily removed by phagocytic cells without causing an inflammatory response.

Necrosis, on the other hand, is a form of cell death that occurs as a result of acute tissue injury or overwhelming stress. During necrosis, the cell's membrane becomes damaged and the contents of the cell are released into the surrounding tissue, causing an inflammatory response.

There are also other forms of cell death, such as autophagy, which is a process by which cells break down their own organelles and proteins to recycle nutrients and maintain energy homeostasis, and pyroptosis, which is a form of programmed cell death that occurs in response to infection and involves the activation of inflammatory caspases.

Cell death is an important process in many physiological and pathological processes, including development, tissue homeostasis, and disease. Dysregulation of cell death can contribute to the development of various diseases, including cancer, neurodegenerative disorders, and autoimmune diseases.

The term "diabetic foot" refers to a condition that affects the feet of people with diabetes, particularly when the disease is not well-controlled. It is characterized by a combination of nerve damage (neuropathy) and poor circulation (peripheral artery disease) in the feet and lower legs.

Neuropathy can cause numbness, tingling, or pain in the feet, making it difficult for people with diabetes to feel injuries, cuts, blisters, or other foot problems. Poor circulation makes it harder for wounds to heal and increases the risk of infection.

Diabetic foot ulcers are a common complication of diabetic neuropathy and can lead to serious infections, hospitalization, and even amputation if not treated promptly and effectively. Preventive care, including regular foot exams, proper footwear, and good blood glucose control, is essential for people with diabetes to prevent or manage diabetic foot problems.

Contrast sensitivity is a measure of the ability to distinguish between an object and its background based on differences in contrast, rather than differences in luminance. Contrast refers to the difference in light intensity between an object and its immediate surroundings. Contrast sensitivity is typically measured using specially designed charts that have patterns of parallel lines with varying widths and contrast levels.

In clinical settings, contrast sensitivity is often assessed as part of a comprehensive visual examination. Poor contrast sensitivity can affect a person's ability to perform tasks such as reading, driving, or distinguishing objects from their background, especially in low-light conditions. Reduced contrast sensitivity is a common symptom of various eye conditions, including cataracts, glaucoma, and age-related macular degeneration.

Neuroprotective agents are substances that protect neurons or nerve cells from damage, degeneration, or death caused by various factors such as trauma, inflammation, oxidative stress, or excitotoxicity. These agents work through different mechanisms, including reducing the production of free radicals, inhibiting the release of glutamate (a neurotransmitter that can cause cell damage in high concentrations), promoting the growth and survival of neurons, and preventing apoptosis (programmed cell death). Neuroprotective agents have been studied for their potential to treat various neurological disorders, including stroke, traumatic brain injury, Parkinson's disease, Alzheimer's disease, and multiple sclerosis. However, more research is needed to fully understand their mechanisms of action and to develop effective therapies.

Postoperative complications refer to any unfavorable condition or event that occurs during the recovery period after a surgical procedure. These complications can vary in severity and may include, but are not limited to:

1. Infection: This can occur at the site of the incision or inside the body, such as pneumonia or urinary tract infection.
2. Bleeding: Excessive bleeding (hemorrhage) can lead to a drop in blood pressure and may require further surgical intervention.
3. Blood clots: These can form in the deep veins of the legs (deep vein thrombosis) and can potentially travel to the lungs (pulmonary embolism).
4. Wound dehiscence: This is when the surgical wound opens up, which can lead to infection and further complications.
5. Pulmonary issues: These include atelectasis (collapsed lung), pneumonia, or respiratory failure.
6. Cardiovascular problems: These include abnormal heart rhythms (arrhythmias), heart attack, or stroke.
7. Renal failure: This can occur due to various reasons such as dehydration, blood loss, or the use of certain medications.
8. Pain management issues: Inadequate pain control can lead to increased stress, anxiety, and decreased mobility.
9. Nausea and vomiting: These can be caused by anesthesia, opioid pain medication, or other factors.
10. Delirium: This is a state of confusion and disorientation that can occur in the elderly or those with certain medical conditions.

Prompt identification and management of these complications are crucial to ensure the best possible outcome for the patient.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

The Peroneal nerve, also known as the common fibular nerve, is a branch of the sciatic nerve that supplies the muscles of the lower leg and provides sensation to the skin on the outer part of the lower leg and the top of the foot. It winds around the neck of the fibula (calf bone) and can be vulnerable to injury in this area, leading to symptoms such as weakness or numbness in the foot and leg.

The Peripheral Nervous System (PNS) is that part of the nervous system which lies outside of the brain and spinal cord. It includes all the nerves and ganglia ( clusters of neurons) outside of the central nervous system (CNS). The PNS is divided into two components: the somatic nervous system and the autonomic nervous system.

The somatic nervous system is responsible for transmitting sensory information from the skin, muscles, and joints to the CNS, and for controlling voluntary movements of the skeletal muscles.

The autonomic nervous system, on the other hand, controls involuntary actions, such as heart rate, digestion, respiratory rate, salivation, perspiration, pupillary dilation, and sexual arousal. It is further divided into the sympathetic and parasympathetic systems, which generally have opposing effects and maintain homeostasis in the body.

Damage to the peripheral nervous system can result in various medical conditions such as neuropathies, neuritis, plexopathies, and radiculopathies, leading to symptoms like numbness, tingling, pain, weakness, or loss of reflexes in the affected area.

Confocal microscopy is a powerful imaging technique used in medical and biological research to obtain high-resolution, contrast-rich images of thick samples. This super-resolution technology provides detailed visualization of cellular structures and processes at various depths within a specimen.

In confocal microscopy, a laser beam focused through a pinhole illuminates a small spot within the sample. The emitted fluorescence or reflected light from this spot is then collected by a detector, passing through a second pinhole that ensures only light from the focal plane reaches the detector. This process eliminates out-of-focus light, resulting in sharp images with improved contrast compared to conventional widefield microscopy.

By scanning the laser beam across the sample in a raster pattern and collecting fluorescence at each point, confocal microscopy generates optical sections of the specimen. These sections can be combined to create three-dimensional reconstructions, allowing researchers to study cellular architecture and interactions within complex tissues.

Confocal microscopy has numerous applications in medical research, including studying protein localization, tracking intracellular dynamics, analyzing cell morphology, and investigating disease mechanisms at the cellular level. Additionally, it is widely used in clinical settings for diagnostic purposes, such as analyzing skin lesions or detecting pathogens in patient samples.

Sensitivity and specificity are statistical measures used to describe the performance of a diagnostic test or screening tool in identifying true positive and true negative results.

* Sensitivity refers to the proportion of people who have a particular condition (true positives) who are correctly identified by the test. It is also known as the "true positive rate" or "recall." A highly sensitive test will identify most or all of the people with the condition, but may also produce more false positives.
* Specificity refers to the proportion of people who do not have a particular condition (true negatives) who are correctly identified by the test. It is also known as the "true negative rate." A highly specific test will identify most or all of the people without the condition, but may also produce more false negatives.

In medical testing, both sensitivity and specificity are important considerations when evaluating a diagnostic test. High sensitivity is desirable for screening tests that aim to identify as many cases of a condition as possible, while high specificity is desirable for confirmatory tests that aim to rule out the condition in people who do not have it.

It's worth noting that sensitivity and specificity are often influenced by factors such as the prevalence of the condition in the population being tested, the threshold used to define a positive result, and the reliability and validity of the test itself. Therefore, it's important to consider these factors when interpreting the results of a diagnostic test.

X-ray computed tomography (CT or CAT scan) is a medical imaging method that uses computer-processed combinations of many X-ray images taken from different angles to produce cross-sectional (tomographic) images (virtual "slices") of the body. These cross-sectional images can then be used to display detailed internal views of organs, bones, and soft tissues in the body.

The term "computed tomography" is used instead of "CT scan" or "CAT scan" because the machines take a series of X-ray measurements from different angles around the body and then use a computer to process these data to create detailed images of internal structures within the body.

CT scanning is a noninvasive, painless medical test that helps physicians diagnose and treat medical conditions. CT imaging provides detailed information about many types of tissue including lung, bone, soft tissue and blood vessels. CT examinations can be performed on every part of the body for a variety of reasons including diagnosis, surgical planning, and monitoring of therapeutic responses.

In computed tomography (CT), an X-ray source and detector rotate around the patient, measuring the X-ray attenuation at many different angles. A computer uses this data to construct a cross-sectional image by the process of reconstruction. This technique is called "tomography". The term "computed" refers to the use of a computer to reconstruct the images.

CT has become an important tool in medical imaging and diagnosis, allowing radiologists and other physicians to view detailed internal images of the body. It can help identify many different medical conditions including cancer, heart disease, lung nodules, liver tumors, and internal injuries from trauma. CT is also commonly used for guiding biopsies and other minimally invasive procedures.

In summary, X-ray computed tomography (CT or CAT scan) is a medical imaging technique that uses computer-processed combinations of many X-ray images taken from different angles to produce cross-sectional images of the body. It provides detailed internal views of organs, bones, and soft tissues in the body, allowing physicians to diagnose and treat medical conditions.

Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.

Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.

These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.

Schwann cells, also known as neurolemmocytes, are a type of glial cell that form the myelin sheath around peripheral nervous system (PNS) axons, allowing for the rapid and efficient transmission of nerve impulses. These cells play a crucial role in the maintenance and function of the PNS.

Schwann cells originate from the neural crest during embryonic development and migrate to the developing nerves. They wrap around the axons in a spiral fashion, forming multiple layers of myelin, which insulates the nerve fibers and increases the speed of electrical impulse transmission. Each Schwann cell is responsible for myelinating a single segment of an axon, with the gaps between these segments called nodes of Ranvier.

Schwann cells also provide structural support to the neurons and contribute to the regeneration of injured peripheral nerves by helping to guide the regrowth of axons to their targets. Additionally, Schwann cells can participate in immune responses within the PNS, such as releasing cytokines and chemokines to recruit immune cells during injury or infection.

A Severity of Illness Index is a measurement tool used in healthcare to assess the severity of a patient's condition and the risk of mortality or other adverse outcomes. These indices typically take into account various physiological and clinical variables, such as vital signs, laboratory values, and co-morbidities, to generate a score that reflects the patient's overall illness severity.

Examples of Severity of Illness Indices include the Acute Physiology and Chronic Health Evaluation (APACHE) system, the Simplified Acute Physiology Score (SAPS), and the Mortality Probability Model (MPM). These indices are often used in critical care settings to guide clinical decision-making, inform prognosis, and compare outcomes across different patient populations.

It is important to note that while these indices can provide valuable information about a patient's condition, they should not be used as the sole basis for clinical decision-making. Rather, they should be considered in conjunction with other factors, such as the patient's overall clinical presentation, treatment preferences, and goals of care.

I am not aware of a specific medical definition for the term "China." Generally, it is used to refer to:

1. The People's Republic of China (PRC), which is a country in East Asia. It is the most populous country in the world and the fourth largest by geographical area. Its capital city is Beijing.
2. In a historical context, "China" was used to refer to various dynasties and empires that existed in East Asia over thousands of years. The term "Middle Kingdom" or "Zhongguo" (中国) has been used by the Chinese people to refer to their country for centuries.
3. In a more general sense, "China" can also be used to describe products or goods that originate from or are associated with the People's Republic of China.

If you have a specific context in which you encountered the term "China" related to medicine, please provide it so I can give a more accurate response.

Reproducibility of results in a medical context refers to the ability to obtain consistent and comparable findings when a particular experiment or study is repeated, either by the same researcher or by different researchers, following the same experimental protocol. It is an essential principle in scientific research that helps to ensure the validity and reliability of research findings.

In medical research, reproducibility of results is crucial for establishing the effectiveness and safety of new treatments, interventions, or diagnostic tools. It involves conducting well-designed studies with adequate sample sizes, appropriate statistical analyses, and transparent reporting of methods and findings to allow other researchers to replicate the study and confirm or refute the results.

The lack of reproducibility in medical research has become a significant concern in recent years, as several high-profile studies have failed to produce consistent findings when replicated by other researchers. This has led to increased scrutiny of research practices and a call for greater transparency, rigor, and standardization in the conduct and reporting of medical research.

Nerve regeneration is the process of regrowth and restoration of functional nerve connections following damage or injury to the nervous system. This complex process involves various cellular and molecular events, such as the activation of support cells called glia, the sprouting of surviving nerve fibers (axons), and the reformation of neural circuits. The goal of nerve regeneration is to enable the restoration of normal sensory, motor, and autonomic functions impaired due to nerve damage or injury.

In medical terms, sensation refers to the ability to perceive and interpret various stimuli from our environment through specialized receptor cells located throughout the body. These receptors convert physical stimuli such as light, sound, temperature, pressure, and chemicals into electrical signals that are transmitted to the brain via nerves. The brain then interprets these signals, allowing us to experience sensations like sight, hearing, touch, taste, and smell.

There are two main types of sensations: exteroceptive and interoceptive. Exteroceptive sensations involve stimuli from outside the body, such as light, sound, and touch. Interoceptive sensations, on the other hand, refer to the perception of internal bodily sensations, such as hunger, thirst, heartbeat, or emotions.

Disorders in sensation can result from damage to the nervous system, including peripheral nerves, spinal cord, or brain. Examples include numbness, tingling, pain, or loss of sensation in specific body parts, which can significantly impact a person's quality of life and ability to perform daily activities.

Brachial plexus neuropathies refer to a group of conditions that affect the brachial plexus, which is a network of nerves that originates from the spinal cord in the neck and travels down the arm. These nerves are responsible for providing motor and sensory function to the shoulder, arm, and hand.

Brachial plexus neuropathies can occur due to various reasons, including trauma, compression, inflammation, or tumors. The condition can cause symptoms such as pain, numbness, weakness, or paralysis in the affected arm and hand.

The specific medical definition of brachial plexus neuropathies is:

"A group of conditions that affect the brachial plexus, characterized by damage to the nerves that results in motor and/or sensory impairment of the upper limb. The condition can be congenital or acquired, with causes including trauma, compression, inflammation, or tumors."

Treatment outcome is a term used to describe the result or effect of medical treatment on a patient's health status. It can be measured in various ways, such as through symptoms improvement, disease remission, reduced disability, improved quality of life, or survival rates. The treatment outcome helps healthcare providers evaluate the effectiveness of a particular treatment plan and make informed decisions about future care. It is also used in clinical research to compare the efficacy of different treatments and improve patient care.

I'm sorry for any confusion, but Fourier Analysis is not a medical term. It is a mathematical concept used in various scientific fields, including physics, engineering, and signal processing.

Fourier Analysis is a method to decompose functions into sinusoidal components (sines and cosines) of different frequencies. This allows for the representation of a function or a signal as a sum of these frequency components. It's particularly useful in analyzing periodic functions, understanding signals, and solving partial differential equations.

If you have any medical terms you would like me to define, please let me know!

Cell survival refers to the ability of a cell to continue living and functioning normally, despite being exposed to potentially harmful conditions or treatments. This can include exposure to toxins, radiation, chemotherapeutic drugs, or other stressors that can damage cells or interfere with their normal processes.

In scientific research, measures of cell survival are often used to evaluate the effectiveness of various therapies or treatments. For example, researchers may expose cells to a particular drug or treatment and then measure the percentage of cells that survive to assess its potential therapeutic value. Similarly, in toxicology studies, measures of cell survival can help to determine the safety of various chemicals or substances.

It's important to note that cell survival is not the same as cell proliferation, which refers to the ability of cells to divide and multiply. While some treatments may promote cell survival, they may also inhibit cell proliferation, making them useful for treating diseases such as cancer. Conversely, other treatments may be designed to specifically target and kill cancer cells, even if it means sacrificing some healthy cells in the process.

Neuromuscular diseases are a group of disorders that involve the peripheral nervous system, which includes the nerves and muscles outside of the brain and spinal cord. These conditions can affect both children and adults, and they can be inherited or acquired. Neuromuscular diseases can cause a wide range of symptoms, including muscle weakness, numbness, tingling, pain, cramping, and twitching. Some common examples of neuromuscular diseases include muscular dystrophy, amyotrophic lateral sclerosis (ALS), peripheral neuropathy, and myasthenia gravis. The specific symptoms and severity of these conditions can vary widely depending on the underlying cause and the specific muscles and nerves that are affected. Treatment for neuromuscular diseases may include medications, physical therapy, assistive devices, or surgery, depending on the individual case.

Photic stimulation is a medical term that refers to the exposure of the eyes to light, specifically repetitive pulses of light, which is used as a method in various research and clinical settings. In neuroscience, it's often used in studies related to vision, circadian rhythms, and brain function.

In a clinical context, photic stimulation is sometimes used in the diagnosis of certain medical conditions such as seizure disorders (like epilepsy). By observing the response of the brain to this light stimulus, doctors can gain valuable insights into the functioning of the brain and the presence of any neurological disorders.

However, it's important to note that photic stimulation should be conducted under the supervision of a trained healthcare professional, as improper use can potentially trigger seizures in individuals who are susceptible to them.

Electromyography (EMG) is a medical diagnostic procedure that measures the electrical activity of skeletal muscles during contraction and at rest. It involves inserting a thin needle electrode into the muscle to record the electrical signals generated by the muscle fibers. These signals are then displayed on an oscilloscope and may be heard through a speaker.

EMG can help diagnose various neuromuscular disorders, such as muscle weakness, numbness, or pain, and can distinguish between muscle and nerve disorders. It is often used in conjunction with other diagnostic tests, such as nerve conduction studies, to provide a comprehensive evaluation of the nervous system.

EMG is typically performed by a neurologist or a physiatrist, and the procedure may cause some discomfort or pain, although this is usually minimal. The results of an EMG can help guide treatment decisions and monitor the progression of neuromuscular conditions over time.

Neuritis is a general term that refers to inflammation of a nerve or nerves, often causing pain, loss of function, and/or sensory changes. It can affect any part of the nervous system, including the peripheral nerves (those outside the brain and spinal cord) or the cranial nerves (those that serve the head and neck). Neuritis may result from various causes, such as infections, autoimmune disorders, trauma, toxins, or metabolic conditions. The specific symptoms and treatment depend on the underlying cause and the affected nerve(s).

Sensory thresholds are the minimum levels of stimulation that are required to produce a sensation in an individual, as determined through psychophysical testing. These tests measure the point at which a person can just barely detect the presence of a stimulus, such as a sound, light, touch, or smell.

There are two types of sensory thresholds: absolute and difference. Absolute threshold is the minimum level of intensity required to detect a stimulus 50% of the time. Difference threshold, also known as just noticeable difference (JND), is the smallest change in intensity that can be detected between two stimuli.

Sensory thresholds can vary between individuals and are influenced by factors such as age, attention, motivation, and expectations. They are often used in clinical settings to assess sensory function and diagnose conditions such as hearing or vision loss.

The Tibial nerve is a major branch of the sciatic nerve that originates in the lower back and runs through the buttock and leg. It provides motor (nerve impulses that control muscle movement) and sensory (nerve impulses that convey information about touch, temperature, and pain) innervation to several muscles and skin regions in the lower limb.

More specifically, the Tibial nerve supplies the following structures:

1. Motor Innervation: The Tibial nerve provides motor innervation to the muscles in the back of the leg (posterior compartment), including the calf muscles (gastrocnemius and soleus) and the small muscles in the foot (intrinsic muscles). These muscles are responsible for plantarflexion (pointing the foot downward) and inversion (turning the foot inward) of the foot.
2. Sensory Innervation: The Tibial nerve provides sensory innervation to the skin on the sole of the foot, as well as the heel and some parts of the lower leg.

The Tibial nerve travels down the leg, passing behind the knee and through the calf, where it eventually joins with the common fibular (peroneal) nerve to form the tibial-fibular trunk. This trunk then divides into several smaller nerves that innervate the foot's intrinsic muscles and skin.

Damage or injury to the Tibial nerve can result in various symptoms, such as weakness or paralysis of the calf and foot muscles, numbness or tingling sensations in the sole of the foot, and difficulty walking or standing on tiptoes.

A foot ulcer is a wound or sore on the foot that occurs most commonly in people with diabetes, but can also affect other individuals with poor circulation or nerve damage. These ulcers can be challenging to heal and are prone to infection, making it essential for individuals with foot ulcers to seek medical attention promptly.

Foot ulcers typically develop due to prolonged pressure on bony prominences of the foot, leading to breakdown of the skin and underlying tissues. The development of foot ulcers can be attributed to several factors, including:

1. Neuropathy (nerve damage): This condition causes a loss of sensation in the feet, making it difficult for individuals to feel pain or discomfort associated with pressure points, leading to the formation of ulcers.
2. Peripheral artery disease (PAD): Reduced blood flow to the lower extremities can impair wound healing and make the body more susceptible to infection.
3. Deformities: Structural foot abnormalities, such as bunions or hammertoes, can cause increased pressure on specific areas of the foot, increasing the risk of ulcer formation.
4. Poorly fitting shoes: Shoes that are too tight, narrow, or ill-fitting can create friction and pressure points, contributing to the development of foot ulcers.
5. Trauma: Injuries or trauma to the feet can lead to the formation of ulcers, particularly in individuals with neuropathy who may not feel the initial pain associated with the injury.
6. Foot care neglect: Failure to inspect and care for the feet regularly can result in undetected wounds or sores that progress into ulcers.

Foot ulcers are classified based on their depth, severity, and extent of tissue involvement. Proper assessment, treatment, and prevention strategies are crucial in managing foot ulcers and minimizing the risk of complications such as infection, gangrene, and amputation.

"Macaca mulatta" is the scientific name for the Rhesus macaque, a species of monkey that is native to South, Central, and Southeast Asia. They are often used in biomedical research due to their genetic similarity to humans.

The median nerve is one of the major nerves in the human body, providing sensation and motor function to parts of the arm and hand. It originates from the brachial plexus, a network of nerves that arise from the spinal cord in the neck. The median nerve travels down the arm, passing through the cubital tunnel at the elbow, and continues into the forearm and hand.

In the hand, the median nerve supplies sensation to the palm side of the thumb, index finger, middle finger, and half of the ring finger. It also provides motor function to some of the muscles that control finger movements, allowing for flexion of the fingers and opposition of the thumb.

Damage to the median nerve can result in a condition called carpal tunnel syndrome, which is characterized by numbness, tingling, and weakness in the hand and fingers.

"Long-Evans" is a strain of laboratory rats commonly used in scientific research. They are named after their developers, the scientists Long and Evans. This strain is albino, with a brownish-black hood over their eyes and ears, and they have an agouti (salt-and-pepper) color on their backs. They are often used as a model organism due to their size, ease of handling, and genetic similarity to humans. However, I couldn't find any specific medical definition related to "Long-Evans rats" as they are not a medical condition or disease.

Axonal transport is the controlled movement of materials and organelles within axons, which are the nerve fibers of neurons (nerve cells). This intracellular transport system is essential for maintaining the structural and functional integrity of axons, particularly in neurons with long axonal processes. There are two types of axonal transport: anterograde transport, which moves materials from the cell body toward the synaptic terminals, and retrograde transport, which transports materials from the synaptic terminals back to the cell body. Anterograde transport is typically slower than retrograde transport and can be divided into fast and slow components based on velocity. Fast anterograde transport moves vesicles containing neurotransmitters and their receptors, as well as mitochondria and other organelles, at speeds of up to 400 mm/day. Slow anterograde transport moves cytoskeletal elements, proteins, and RNA at speeds of 1-10 mm/day. Retrograde transport is primarily responsible for recycling membrane components, removing damaged organelles, and transmitting signals from the axon terminal to the cell body. Dysfunctions in axonal transport have been implicated in various neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS).

"Vasa nervorum" is a term used in anatomical and medical contexts to refer to the blood vessels that supply nerves with oxygen and nutrients. The term comes from Latin, where "vasa" means "vessels" or "ducts," and "nervorum" refers to "of the nerves."

These tiny blood vessels run within the nerve fascicles, which are bundles of nerve fibers surrounded by a layer of connective tissue. The vasa nervorum supply the nerve fibers, the supporting cells (such as Schwann cells), and the surrounding connective tissues with oxygen and nutrients. They also help remove waste products generated by normal cellular metabolism.

The health and functionality of the vasa nervorum are crucial for maintaining proper nerve function. Conditions that affect blood flow in these vessels, such as vasculitis or diabetes, can lead to nerve damage and various neurological disorders.

Medical Definition of Optical Fibers:

Optical fibers are thin, transparent strands of glass or plastic fiber that are designed to transmit light along their length. In the medical field, optical fibers are used in various applications such as illumination, imaging, and data transmission. For instance, they are used in flexible endoscopes to provide illumination and visualization inside the body during diagnostic or surgical procedures. They are also used in optical communication systems for transmitting information in the form of light signals within medical devices or between medical facilities. The use of optical fibers allows for minimally invasive procedures, improved image quality, and increased data transmission rates.

A dependovirus, also known as a dependent adenovirus or satellite adenovirus, is a type of virus that requires the presence of another virus, specifically an adenovirus, to replicate. Dependoviruses are small, non-enveloped viruses with a double-stranded DNA genome. They cannot complete their replication cycle without the help of an adenovirus, which provides necessary functions for the dependovirus to replicate.

Dependoviruses are clinically significant because they can cause disease in humans, particularly in individuals with weakened immune systems. In some cases, dependoviruses may also affect the severity and outcome of adenovirus infections. However, it is important to note that not all adenovirus infections are associated with dependovirus co-infections.

Myelinated nerve fibers are neuronal processes that are surrounded by a myelin sheath, a fatty insulating substance that is produced by Schwann cells in the peripheral nervous system and oligodendrocytes in the central nervous system. This myelin sheath helps to increase the speed of electrical impulse transmission, also known as action potentials, along the nerve fiber. The myelin sheath has gaps called nodes of Ranvier where the electrical impulses can jump from one node to the next, which also contributes to the rapid conduction of signals. Myelinated nerve fibers are typically found in the peripheral nerves and the optic nerve, but not in the central nervous system (CNS) tracts that are located within the brain and spinal cord.

The term "family" in a medical context often refers to a group of individuals who are related by blood, marriage, or adoption and who consider themselves to be a single household. This can include spouses, parents, children, siblings, grandparents, and other extended family members. In some cases, the term may also be used more broadly to refer to any close-knit group of people who provide emotional and social support for one another, regardless of their biological or legal relationship.

In healthcare settings, understanding a patient's family dynamics can be important for providing effective care. Family members may be involved in decision-making about medical treatments, providing care and support at home, and communicating with healthcare providers. Additionally, cultural beliefs and values within families can influence health behaviors and attitudes towards medical care, making it essential for healthcare professionals to take a culturally sensitive approach when working with patients and their families.

Ataxia is a medical term that refers to a group of disorders affecting coordination, balance, and speech. It is characterized by a lack of muscle control during voluntary movements, causing unsteady or awkward movements, and often accompanied by tremors. Ataxia can affect various parts of the body, such as the limbs, trunk, eyes, and speech muscles. The condition can be congenital or acquired, and it can result from damage to the cerebellum, spinal cord, or sensory nerves. There are several types of ataxia, including hereditary ataxias, degenerative ataxias, cerebellar ataxias, and acquired ataxias, each with its own specific causes, symptoms, and prognosis. Treatment for ataxia typically focuses on managing symptoms and improving quality of life, as there is no cure for most forms of the disorder.

An abnormal reflex in a medical context refers to an involuntary and exaggerated response or lack of response to a stimulus that is not expected in the normal physiological range. These responses can be indicative of underlying neurological disorders or damage to the nervous system. Examples include hyperreflexia (overactive reflexes) and hyporeflexia (underactive reflexes). The assessment of reflexes is an important part of a physical examination, as it can provide valuable information about the functioning of the nervous system.

Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.

Hyperesthesia is a medical term that refers to an increased sensitivity to sensory stimuli, including touch, pain, or temperature. It can affect various parts of the body and can be caused by different conditions, such as nerve damage, multiple sclerosis, or complex regional pain syndrome. Hyperesthesia can manifest as a heightened awareness of sensations, which can be painful or uncomfortable, and may interfere with daily activities. It is essential to consult a healthcare professional for an accurate diagnosis and appropriate treatment if experiencing symptoms of hyperesthesia.

Mononeuropathy is a medical condition that refers to damage or dysfunction affecting a single peripheral nerve, outside of the brain and spinal cord. This can result in weakness, numbness, or pain in the area served by that specific nerve. Mononeuropathies can occur due to various reasons such as trauma, compression, infection, or systemic diseases like diabetes. The symptoms and severity may vary depending on the type and location of the affected nerve.

I couldn't find a medical definition specifically for "Diabetes Mellitus, Experimental." However, I can provide you with information about experimental diabetes research and its relevance to understanding the disease.

Experimental diabetes models are used in biomedical research to study the pathophysiology of diabetes mellitus and to test potential therapies or treatments. These models can be broadly categorized into two types: chemically-induced and genetically modified.

1. Chemically-induced diabetes models: These involve administering chemicals, such as alloxan or streptozotocin, to animals (commonly mice or rats) to destroy their pancreatic β-cells, which produce insulin. This results in hyperglycemia and symptoms similar to those seen in type 1 diabetes in humans.
2. Genetically modified diabetes models: These involve altering the genes of animals (commonly mice) to create a diabetes phenotype. Examples include non-obese diabetic (NOD) mice, which develop an autoimmune form of diabetes similar to human type 1 diabetes, and various strains of obese mice with insulin resistance, such as ob/ob or db/db mice, which model aspects of type 2 diabetes.

These experimental models help researchers better understand the mechanisms behind diabetes development and progression, identify new therapeutic targets, and test potential treatments before moving on to human clinical trials. However, it's essential to recognize that these models may not fully replicate all aspects of human diabetes, so findings from animal studies should be interpreted with caution.

Spinal ganglia, also known as dorsal root ganglia, are clusters of nerve cell bodies located in the peripheral nervous system. They are situated along the length of the spinal cord and are responsible for transmitting sensory information from the body to the brain. Each spinal ganglion contains numerous neurons, or nerve cells, with long processes called axons that extend into the periphery and innervate various tissues and organs. The cell bodies within the spinal ganglia receive sensory input from these axons and transmit this information to the central nervous system via the dorsal roots of the spinal nerves. This allows the brain to interpret and respond to a wide range of sensory stimuli, including touch, temperature, pain, and proprioception (the sense of the position and movement of one's body).

Neurotoxicity syndromes refer to a group of conditions caused by exposure to neurotoxins, which are substances that can damage the structure or function of the nervous system. Neurotoxicity syndromes can affect both the central and peripheral nervous systems and may cause a wide range of symptoms depending on the type and severity of the exposure.

Symptoms of neurotoxicity syndromes may include:

* Headache
* Dizziness
* Tremors or shaking
* Difficulty with coordination or balance
* Numbness or tingling in the hands and feet
* Vision problems
* Memory loss or difficulty concentrating
* Seizures or convulsions
* Mood changes, such as depression or anxiety

Neurotoxicity syndromes can be caused by exposure to a variety of substances, including heavy metals (such as lead, mercury, and arsenic), pesticides, solvents, and certain medications. In some cases, neurotoxicity syndromes may be reversible with treatment, while in other cases, the damage may be permanent.

Prevention is key in avoiding neurotoxicity syndromes, and it is important to follow safety guidelines when working with or around potential neurotoxins. If exposure does occur, prompt medical attention is necessary to minimize the risk of long-term health effects.

The brain is the central organ of the nervous system, responsible for receiving and processing sensory information, regulating vital functions, and controlling behavior, movement, and cognition. It is divided into several distinct regions, each with specific functions:

1. Cerebrum: The largest part of the brain, responsible for higher cognitive functions such as thinking, learning, memory, language, and perception. It is divided into two hemispheres, each controlling the opposite side of the body.
2. Cerebellum: Located at the back of the brain, it is responsible for coordinating muscle movements, maintaining balance, and fine-tuning motor skills.
3. Brainstem: Connects the cerebrum and cerebellum to the spinal cord, controlling vital functions such as breathing, heart rate, and blood pressure. It also serves as a relay center for sensory information and motor commands between the brain and the rest of the body.
4. Diencephalon: A region that includes the thalamus (a major sensory relay station) and hypothalamus (regulates hormones, temperature, hunger, thirst, and sleep).
5. Limbic system: A group of structures involved in emotional processing, memory formation, and motivation, including the hippocampus, amygdala, and cingulate gyrus.

The brain is composed of billions of interconnected neurons that communicate through electrical and chemical signals. It is protected by the skull and surrounded by three layers of membranes called meninges, as well as cerebrospinal fluid that provides cushioning and nutrients.

I'm sorry for any confusion, but "Goldfish" is not a term used in medical definitions. Goldfish are small domesticated fish that are often kept as pets. They belong to the family Cyprinidae and the genus Carassius. The most common species of goldfish is Carassius auratus. If you have any questions about goldfish or their care, I might be able to help with some general information, but for specific medical concerns, it would be best to consult a veterinarian.

In medical terms, the foot is the part of the lower limb that is distal to the leg and below the ankle, extending from the tarsus to the toes. It is primarily responsible for supporting body weight and facilitating movement through push-off during walking or running. The foot is a complex structure made up of 26 bones, 33 joints, and numerous muscles, tendons, ligaments, and nerves that work together to provide stability, balance, and flexibility. It can be divided into three main parts: the hindfoot, which contains the talus and calcaneus (heel) bones; the midfoot, which includes the navicular, cuboid, and cuneiform bones; and the forefoot, which consists of the metatarsals and phalanges that form the toes.

Antitubercular agents, also known as anti-tuberculosis drugs or simply TB drugs, are a category of medications specifically used for the treatment and prevention of tuberculosis (TB), a bacterial infection caused by Mycobacterium tuberculosis. These drugs target various stages of the bacteria's growth and replication process to eradicate it from the body or prevent its spread.

There are several first-line antitubercular agents, including:

1. Isoniazid (INH): This is a bactericidal drug that inhibits the synthesis of mycolic acids, essential components of the mycobacterial cell wall. It is primarily active against actively growing bacilli.
2. Rifampin (RIF) or Rifampicin: A bactericidal drug that inhibits DNA-dependent RNA polymerase, preventing the transcription of genetic information into mRNA. This results in the interruption of protein synthesis and ultimately leads to the death of the bacteria.
3. Ethambutol (EMB): A bacteriostatic drug that inhibits the arabinosyl transferase enzyme, which is responsible for the synthesis of arabinan, a crucial component of the mycobacterial cell wall. It is primarily active against actively growing bacilli.
4. Pyrazinamide (PZA): A bactericidal drug that inhibits the synthesis of fatty acids and mycolic acids in the mycobacterial cell wall, particularly under acidic conditions. PZA is most effective during the initial phase of treatment when the bacteria are in a dormant or slow-growing state.

These first-line antitubercular agents are often used together in a combination therapy to ensure complete eradication of the bacteria and prevent the development of drug-resistant strains. Treatment duration typically lasts for at least six months, with the initial phase consisting of daily doses of INH, RIF, EMB, and PZA for two months, followed by a continuation phase of INH and RIF for four months.

Second-line antitubercular agents are used when patients have drug-resistant TB or cannot tolerate first-line drugs. These include drugs like aminoglycosides (e.g., streptomycin, amikacin), fluoroquinolones (e.g., ofloxacin, moxifloxacin), and injectable bacteriostatic agents (e.g., capreomycin, ethionamide).

It is essential to closely monitor patients undergoing antitubercular therapy for potential side effects and ensure adherence to the treatment regimen to achieve optimal outcomes and prevent the development of drug-resistant strains.

Diabetes Mellitus, Type 1 is a chronic autoimmune disease characterized by the destruction of insulin-producing beta cells in the pancreas, leading to an absolute deficiency of insulin. This results in an inability to regulate blood glucose levels, causing hyperglycemia (high blood sugar). Type 1 diabetes typically presents in childhood or early adulthood, although it can develop at any age. It is usually managed with regular insulin injections or the use of an insulin pump, along with monitoring of blood glucose levels and adjustments to diet and physical activity. Uncontrolled type 1 diabetes can lead to serious complications such as kidney damage, nerve damage, blindness, and cardiovascular disease.

Western blotting is a laboratory technique used in molecular biology to detect and quantify specific proteins in a mixture of many different proteins. This technique is commonly used to confirm the expression of a protein of interest, determine its size, and investigate its post-translational modifications. The name "Western" blotting distinguishes this technique from Southern blotting (for DNA) and Northern blotting (for RNA).

The Western blotting procedure involves several steps:

1. Protein extraction: The sample containing the proteins of interest is first extracted, often by breaking open cells or tissues and using a buffer to extract the proteins.
2. Separation of proteins by electrophoresis: The extracted proteins are then separated based on their size by loading them onto a polyacrylamide gel and running an electric current through the gel (a process called sodium dodecyl sulfate-polyacrylamide gel electrophoresis or SDS-PAGE). This separates the proteins according to their molecular weight, with smaller proteins migrating faster than larger ones.
3. Transfer of proteins to a membrane: After separation, the proteins are transferred from the gel onto a nitrocellulose or polyvinylidene fluoride (PVDF) membrane using an electric current in a process called blotting. This creates a replica of the protein pattern on the gel but now immobilized on the membrane for further analysis.
4. Blocking: The membrane is then blocked with a blocking agent, such as non-fat dry milk or bovine serum albumin (BSA), to prevent non-specific binding of antibodies in subsequent steps.
5. Primary antibody incubation: A primary antibody that specifically recognizes the protein of interest is added and allowed to bind to its target protein on the membrane. This step may be performed at room temperature or 4°C overnight, depending on the antibody's properties.
6. Washing: The membrane is washed with a buffer to remove unbound primary antibodies.
7. Secondary antibody incubation: A secondary antibody that recognizes the primary antibody (often coupled to an enzyme or fluorophore) is added and allowed to bind to the primary antibody. This step may involve using a horseradish peroxidase (HRP)-conjugated or alkaline phosphatase (AP)-conjugated secondary antibody, depending on the detection method used later.
8. Washing: The membrane is washed again to remove unbound secondary antibodies.
9. Detection: A detection reagent is added to visualize the protein of interest by detecting the signal generated from the enzyme-conjugated or fluorophore-conjugated secondary antibody. This can be done using chemiluminescent, colorimetric, or fluorescent methods.
10. Analysis: The resulting image is analyzed to determine the presence and quantity of the protein of interest in the sample.

Western blotting is a powerful technique for identifying and quantifying specific proteins within complex mixtures. It can be used to study protein expression, post-translational modifications, protein-protein interactions, and more. However, it requires careful optimization and validation to ensure accurate and reproducible results.

'DBA' is an abbreviation for 'Database of Genotypes and Phenotypes,' but in the context of "Inbred DBA mice," it refers to a specific strain of laboratory mice that have been inbred for many generations. The DBA strain is one of the oldest inbred strains, and it was established in 1909 by C.C. Little at the Bussey Institute of Harvard University.

The "Inbred DBA" mice are genetically identical mice that have been produced by brother-sister matings for more than 20 generations. This extensive inbreeding results in a homozygous population, where all members of the strain have the same genetic makeup. The DBA strain is further divided into several sub-strains, including DBA/1, DBA/2, and DBA/J, among others.

DBA mice are known for their black coat color, which can fade to gray with age, and they exhibit a range of phenotypic traits that make them useful for research purposes. For example, DBA mice have a high incidence of retinal degeneration, making them a valuable model for studying eye diseases. They also show differences in behavior, immune response, and susceptibility to various diseases compared to other inbred strains.

In summary, "Inbred DBA" mice are a specific strain of laboratory mice that have been inbred for many generations, resulting in a genetically identical population with distinct phenotypic traits. They are widely used in biomedical research to study various diseases and biological processes.

Reactive Oxygen Species (ROS) are highly reactive molecules containing oxygen, including peroxides, superoxide, hydroxyl radical, and singlet oxygen. They are naturally produced as byproducts of normal cellular metabolism in the mitochondria, and can also be generated by external sources such as ionizing radiation, tobacco smoke, and air pollutants. At low or moderate concentrations, ROS play important roles in cell signaling and homeostasis, but at high concentrations, they can cause significant damage to cell structures, including lipids, proteins, and DNA, leading to oxidative stress and potential cell death.

Prevalence, in medical terms, refers to the total number of people in a given population who have a particular disease or condition at a specific point in time, or over a specified period. It is typically expressed as a percentage or a ratio of the number of cases to the size of the population. Prevalence differs from incidence, which measures the number of new cases that develop during a certain period.

Paclitaxel is a chemotherapeutic agent derived from the bark of the Pacific yew tree (Taxus brevifolia). It is an antimicrotubule agent that promotes the assembly and stabilization of microtubules, thereby interfering with the normal dynamic reorganization of the microtubule network that is essential for cell division.

Paclitaxel is used in the treatment of various types of cancer including ovarian, breast, lung, and pancreatic cancers. It works by inhibiting the disassembly of microtubules, which prevents the separation of chromosomes during mitosis, leading to cell cycle arrest and apoptosis (programmed cell death).

Common side effects of paclitaxel include neutropenia (low white blood cell count), anemia (low red blood cell count), alopecia (hair loss), peripheral neuropathy (nerve damage causing numbness or tingling in the hands and feet), myalgias (muscle pain), arthralgias (joint pain), and hypersensitivity reactions.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

Hyperalgesia is a medical term that describes an increased sensitivity to pain. It occurs when the nervous system, specifically the nociceptors (pain receptors), become excessively sensitive to stimuli. This means that a person experiences pain from a stimulus that normally wouldn't cause pain or experiences pain that is more intense than usual. Hyperalgesia can be a result of various conditions such as nerve damage, inflammation, or certain medications. It's an important symptom to monitor in patients with chronic pain conditions, as it may indicate the development of tolerance or addiction to pain medication.

Radial neuropathy, also known as radial nerve palsy, refers to damage or dysfunction of the radial nerve. The radial nerve provides motor function to the muscles in the back of the arm and sensation to the back of the hand and forearm. Damage to this nerve can result in weakness or paralysis of the wrist and finger extensors, causing difficulty with extending the wrist, fingers, and thumb. Additionally, there may be numbness or tingling sensations in the back of the hand and forearm. Radial neuropathy can occur due to various reasons such as trauma, compression, or certain medical conditions like diabetes.

Oxidative stress is defined as an imbalance between the production of reactive oxygen species (free radicals) and the body's ability to detoxify them or repair the damage they cause. This imbalance can lead to cellular damage, oxidation of proteins, lipids, and DNA, disruption of cellular functions, and activation of inflammatory responses. Prolonged or excessive oxidative stress has been linked to various health conditions, including cancer, cardiovascular diseases, neurodegenerative disorders, and aging-related diseases.

Gene frequency, also known as allele frequency, is a measure in population genetics that reflects the proportion of a particular gene or allele (variant of a gene) in a given population. It is calculated as the number of copies of a specific allele divided by the total number of all alleles at that genetic locus in the population.

For example, if we consider a gene with two possible alleles, A and a, the gene frequency of allele A (denoted as p) can be calculated as follows:

p = (number of copies of allele A) / (total number of all alleles at that locus)

Similarly, the gene frequency of allele a (denoted as q) would be:

q = (number of copies of allele a) / (total number of all alleles at that locus)

Since there are only two possible alleles for this gene in this example, p + q = 1. These frequencies can help researchers understand genetic diversity and evolutionary processes within populations.

Organoplatinum compounds are a group of chemical substances that contain at least one carbon-platinum bond. These compounds have been widely studied and used in the field of medicine, particularly in cancer chemotherapy. The most well-known organoplatinum compound is cisplatin, which is a platinum-based drug used to treat various types of cancers such as testicular, ovarian, bladder, and lung cancers. Cisplatin works by forming crosslinks with the DNA of cancer cells, disrupting their ability to replicate and ultimately leading to cell death. Other examples of organoplatinum compounds used in cancer treatment include carboplatin and oxaliplatin.

... optic neuropathy are typically classified as either anterior ischemic optic neuropathy or posterior ischemic optic neuropathy ... Ischemic optic neuropathy (ION) is the loss of structure and function of a portion of the optic nerve due to obstruction of ... "Chapter 7: Ischemic Optic Neuropathy." Walsh and Hoyt's Clinical Neuro-ophthalmology. Ed. Neil R. Miller, Frank Burton Walsh, ... "Ischemic Optic Neuropathy: Abstract." Seminars in Neurology. By Monica Rodriguez Fontal, John B. Kerrison, and Reinaldo Garcia ...
Ischemic injury to the optic nerve causes inflammation and swelling. Because the posterior optic nerve passes through the optic ... While anterior ischemic optic neuropathy (AION) appears to be more common than PION after cardiac surgery, PION is relatively ... Posterior ischemic optic neuropathy (PION) is a medical condition characterized by damage to the retrobulbar portion of the ... In contrast, anterior ischemic optic neuropathy (AION) is distinguished from PION by the fact that AION occurs spontaneously ...
... (AION) is a medical condition involving loss of vision caused by damage to the optic nerve ... Nonarteritic anterior ischemic optic neuropathy is an isolated white-matter stroke of the optic nerve (ON). NAION is the most ... IONDT(The Ischemic Optic Neuropathy Decompression Trial) Study Liu, Bing; Yu, Ying; Liu, Wen; Deng, Tuo; Xiang, Daoman (2021 ... Sohan Singh Hayreh: Ischemic Optic Neuropathies. Springer, 2011. ISBN 978-3-642-11849-4 (Print); ISBN 978-3-642-11852-4 (eBook ...
... or even regenerate new fibers within the optic nerve.[citation needed] Sohan Hayreh, "Ischemic optic neuropathy", Progress in ... Arteritic anterior ischemic optic neuropathy (AAION or arteritic AION) is the cause of vision loss that occurs in temporal ... Arteritic AION falls under the general category of anterior ischemic optic neuropathy, which also includes non-arteritic AION. ... article published in March 2009 described the latest information on arteritic and non-arteritic ischemic optic neuropathy, both ...
Rizzo JF, Lessell S (1991). "Optic neuritis and ischemic optic neuropathy. Overlapping clinical profiles". Arch. Ophthalmol. ... or ischemic optic neuropathy due to thrombosis or embolism of the vessel that supplies the optic nerve. Up to 50% of patients ... Biousse, Valérie; Campion, Edward W.; Newman, Nancy J. (2015). "Ischemic Optic Neuropathies". New England Journal of Medicine. ... Optic neuropathy Visual snow Petzold, A; Fraser, CL; Abegg, M; et al. (September 2022). Diagnosis and classification of optic ...
An ischemic optic neuropathy may eventually occur. Severe ipsilateral or bilateral carotid artery stenosis or occlusion is the ... Anterior segment ischemic syndrome is a similar ischemic condition of anterior segment usually seen in post-surgical cases. ... Those with ocular ischemic syndrome are typically between the ages of 50 and 80 (patients over 65); twice as many men as women ... "Ocular Ischemic Syndrome." Archived 2009-09-27 at the Wayback Machine Accessed October 25, 2006. Chen KJ, Chen SN, Kao LY, Ho ...
Beck, RW; Servais, GE; Hayreh, SS (1987). "Anterior ischemic optic neuropathy. IX. Cup-to-disc ratio and its role in ... the optic disc and the optic nerve, retinal and choroidal vascular disorders, glaucomatous optic neuropathy, fundus changes in ... Hayreh, Sohan Singh (2009). "Ischemic optic neuropathy". Progress in Retinal and Eye Research. 28 (1): 34-62. doi:10.1016/j. ... Hayreh, S S (1974). "Anterior ischaemic optic neuropathy. III. Treatment, prophylaxis, and differential diagnosis". British ...
Ischemic Optic Neuropathy Decompression Trial Research Group (1995). "Optic nerve decompression surgery for nonarteritic ... the data center for the Ischemic Optic Neuropathy Decompression Trial (IONDT) and the Surgical Treatments Outcomes Project for ... anterior ischemic optic neuropathy (NAION) is not effective and may be harmful". JAMA. 273 (8): 170-179. doi:10.1001/jama. ...
Anterior ischemic optic neuropathy (AION) is a potential complication. Optic disc drusen are found clinically in about 1% of ... Purvin V, King R, Kawasaki A, Yee R (January 2004). "Anterior ischemic optic neuropathy in eyes with optic disc drusen". Arch. ... Gupta, Divya; Chaubey, Anupriya; Singh, Ritu; Gupta, SanjivKumar (2021). "Anterior ischemic optic neuropathy secondary to optic ... Leber Hereditary Optic Neuropathy and linear nevus sebaceous syndrome. Patients with optic disc drusen should be monitored ...
Acute anterior or retrobulbar optic neuritis sometimes associated with pain. Anterior or retrobulbar ischemic optic neuropathy ... Autoimmune optic neuropathy (AON), sometimes called autoimmune optic neuritis, may be a forme fruste of systemic lupus ... associated optic neuropathy. AON is more than the presence of any optic neuritis in a patient with an autoimmune process, as it ... of patients with defined SLE develop an optic neuropathy during the course of their disease. SLE-associated optic neuritis is ...
"Non-Arteritic Anterior Ischemic Optic Neuropathy - Brigham and Women's Hospital". www.brighamandwomens.org. Archived from the ... Penedones A, Alves C, Batel Marques F (February 2020). "Risk of nonarteritic ischaemic optic neuropathy with phosphodiesterase ... non-arteritic anterior ischemic optic neuropathy). Most, but not all, of these patients had underlying anatomic or vascular ...
Anterior ischemic optic neuropathy is commonly known as a "stroke of the optic nerve" and affects the optic nerve head (where ... Optic nerve Optic nerve Human brain dura mater (reflections) Optic nerve Optic nerve Optic nerve Cerebrum.Inferior view.Deep ... optic neuritis, especially in those younger than 50 years of age; and anterior ischemic optic neuropathy, usually in those ... Injury to the optic nerve can be the result of congenital or inheritable problems like Leber's hereditary optic neuropathy, ...
Shape analysis of the peripapillary RPE layer in papilledema and ischemic optic neuropathy. Investigative Ophthalmology & ...
... cases of acute optic neuropathy (specifically anterior ischemic optic neuropathy) have also been reported to occur. Optic nerve ... in some patients with acute optic neuropathy. However, a normal study does not rule out optic neuropathy. Cerebrospinal fluid ( ... ISBN 978-1-934465-30-1. Eye (7 January 2011). "Access : A case of anterior ischemic optic neuropathy associated with Behçet's ... Vasculitis resulting in occlusion of the vessels supplying the optic nerve may be the cause of acute optic neuropathy and ...
These are the two main clinical features that differentiate diabetic papillopathy from anterior ischemic optic neuropathy. ... Diabetic papillopathy has many characteristics similar to Non-arteritic anterior ischemic optic neuropathy (NAION). Diabetic ... 70% type 1, 30% type 2) Optic disc edema (unilateral in 60% cases) Only mild optic nerve dysfunction Disc edema is diagnosed by ... is an ocular complication of diabetes mellitus characterized by optic disc swelling and edema of optic nerve head. The ...
"The prevalence of cupping in end-stage arteritic and nonarteritic anterior ischemic optic neuropathy." Ophthalmology 108, no. 3 ... Danesh-Meyer, Helen (2013). Evaluation of Optic Nerve Morphology in Non-glaucomatous Optic Neuropathies with Quantitative Optic ... Evaluation of optic nerve morphology in non-glaucomatous optic neuropathies with quantitative optic nerve imaging modalities' ... Danesh-Meyer, Helen V. "Radiation-induced optic neuropathy." Journal of Clinical Neuroscience 15, no. 2 (2008): 95-100. Danesh- ...
In ischemic optic neuropathies, there is insufficient blood flow (ischemia) to the optic nerve. The anterior optic nerve is ... Anterior ischemic optic neuropathy (AION) includes diseases that affect the optic nerve head and cause swelling of the optic ... Posterior ischemic optic neuropathy is a syndrome of sudden visual loss with optic neuropathy without initial disc swelling ... Optic nerve damage in most inherited optic neuropathies is permanent and progressive. Leber's hereditary optic neuropathy (LHON ...
Amaurosis Dominant optic atrophy Glaucoma Ischemic optic neuropathy Optic atrophy Toxic and nutritional optic neuropathy ... Leber hereditary optic neuropathy is a condition related to changes in mitochondrial DNA. Although most DNA is packaged in ... Mutations in the MT-ND1, MT-ND4, MT-ND4L, and MT-ND6 genes cause Leber hereditary optic neuropathy. These genes code for the ... Leber's hereditary optic neuropathy at NLM Genetics Home Reference Kerrison JB, Newman NJ (1997). "Clinical spectrum of Leber's ...
Mears KA, Van Stavern GP (July 2009). "Bilateral simultaneous anterior ischaemic optic neuropathy associated with Sticky ...
NEI has supported studies on the treatment of optic nerve disease, including: Ischemic Optic Neuropathy Decompression Trial: ... Optic nerve diseases, like optic neuropathy and optic neuritis, can damage the connection between the eye and the visual ... "Ischemic Optic Neuropathy Decompression Trial - Twenty-Four-Month Update". jamanetwork.com. Retrieved 2023-03-21. Newman, Nancy ... aimed to evaluate the safety and efficacy of optic nerve decompression surgery to treat nonarteritic ischemic optic neuropathy ...
... s are also contraindicated in patients with previous nonarteritic anterior ischaemic optic neuropathy and ... "The phosphodiesterase inhibitors and non-arteritic anterior ischaemic optic neuropathy: increased vigilance is necessary". BJU ... "The phosphodiesterase inhibitors and non-arteritic anterior ischaemic optic neuropathy: increased vigilance is necessary". BJU ... Since 2007 there has been evidence to suggest that PDE5 inhibitors can cause an anterior optic neuropathy, although the ...
In 76% of cases involving the eye, the ophthalmic artery is involved, causing arteritic anterior ischemic optic neuropathy. ... Early and accurate diagnosis is important to prevent ischemic vision loss. Therefore, this condition is considered a medical ...
Optic neuropathy, nonarteritic anterior ischemic optic neuropathy (N-AION), occurs in 1-2% of people and is not dosage ... May 2012). "Amiodarone-associated optic neuropathy: a critical review". The American Journal of Medicine. 125 (5): 447-453. doi ... Bilateral optic disc swelling and mild and reversible visual field defects can also occur. Loss of eyelashes has been linked to ... Fraser AG, McQueen IN, Watt AH, Stephens MR (June 1985). "Peripheral neuropathy during longterm high-dose amiodarone therapy". ...
QPI-007 is a candidate for the treatment of angle-closure glaucoma and Non-arteritic anterior ischaemic optic neuropathy; both ... a progressive optic neurdegeneration frequently associated to increased intraocular pressure; ...
... while patients with an ischemic optic neuropathy may never recover. "Conjugate Gaze Palsies: Neuro-ophthalmologic and Cranial ... For example, optic neuritis, which is caused by inflammation, may heal in just weeks, ...
In October 2013, Schwarz suffered an anterior ischemic optic neuropathy in the right eye and has only had ten percent of his ...
... artery occlusion Branch retinal artery occlusion Branch retinal vein occlusion Eylea Iridodialysis Ischemic optic neuropathy ... It may progress to the more severe ischemic type. CRVO can also cause glaucoma. Despite the role of thrombosis in the ... CRVO without ischemia has better visual prognosis than ischemic CRVO. A systematic review studied the effectiveness of the anti ... CRVO can cause ocular ischemic syndrome. Nonischemic CRVO is the milder form of the disease. ...
Anterior ischemic optic neuropathy (AION), a medical condition involving loss of vision Cleverpath AION Business Rules Expert, ...
... yields no evidence for an increased risk of non-arteritic anterior ischemic optic neuropathy or other adverse ocular events ... It was initially studied for use in hypertension (high blood pressure) and angina pectoris (a symptom of ischaemic heart ...
... ischemic optic neuropathy, retinal detachment, and secondary angle-closure glaucoma may occur. In addition, the medications ... and peripheral neuropathy. As many as 70% of people with lupus have some skin symptoms. The three main categories of lesions ... cranial neuropathy and plexopathy.[citation needed] Neurological disorders contribute to a significant percentage of morbidity ...
... optic neuropathy are typically classified as either anterior ischemic optic neuropathy or posterior ischemic optic neuropathy ... Ischemic optic neuropathy (ION) is the loss of structure and function of a portion of the optic nerve due to obstruction of ... "Chapter 7: Ischemic Optic Neuropathy." Walsh and Hoyts Clinical Neuro-ophthalmology. Ed. Neil R. Miller, Frank Burton Walsh, ... "Ischemic Optic Neuropathy: Abstract." Seminars in Neurology. By Monica Rodriguez Fontal, John B. Kerrison, and Reinaldo Garcia ...
Miller and Smith first used the term ischemic optic neuropathy in 1966, and Hayreh later added the term anterior. ... Field defects typical of ischemic optic neuropathy were probably first described by Knapp in 1875. ... encoded search term (Anterior Ischemic Optic Neuropathy (AION)) and Anterior Ischemic Optic Neuropathy (AION) What to Read Next ... Anterior ischemic optic neuropathy (AION) is the most common cause of acute optic neuropathy in older age groups. It may be ...
Non-arteritic anterior ischemic optic neuropathy is one of the most common conditions affecting the optic nerve in the elderly ... Non-arteritic anterior ischemic optic neuropathy is one of the most common conditions affecting the optic nerve in the. elderly ... Corticosteroid Therapy in Patients with Non-arteritic Anterior Ischemic Optic Neuropathy. Tomislav Vidović ; University of ... anterior ischemic optic neuropathy who were treated with corticosteroid therapy. This prospective study involved. 38 patients, ...
Characteristics of patients with nonarteritic anterior ischemic optic neuropathy eligible for the Ischemic Optic Neuropathy ... Objective: To describe the baseline clinical characteristics of patients in the Ischemic Optic Neuropathy Decompression Trial ( ... surgery or careful follow-up included a diagnosis of acute unilateral nonarteritic anterior ischemic optic neuropathy (NAION), ... Patients: Eligibility criteria for randomization to either optic nerve sheath decompression ...
4.The major features of arteritic-anterior ischemic optic neuropathies and nonarteritic-anterior ischemic optic neuropathies ... 4. The major features of arteritic-anterior ischemic optic neuropathies and nonarteritic-anterior ischemic optic neuropathies. ... Ischaemic optic neuropathy. Indian J. Ophthalmol. 2000. 48. 171. 194. *2. Hayreh. S S. Management of ischemic optic ... Optic nerve head circulation in nonarteritic anterior ischemic optic neuropathy and optic neuritis. Ophthalmology, 2004. 111. ...
Characteristics of patients with nonarteritic anterior ischemic optic neuropathy eligible for the Ischemic Optic Neuropathy ... Anterior ischemic optic neuropathy (AION), is a vision loss-threatening disease caused by an infarction of the optic nerve, ... visual-field defects consistent with ischemic optic neuropathy, and characteristic fundus changes (swollen, pale optic disc ... Anterior ischemic optic neuropathy. Cup-to-disc ratio and its role in pathogenesis. Ophthalmology. 1987; 94:1503-8. [PMID: ...
Anterior ischemic optic neuropathy (AION) is a medical condition involving loss of vision due to damage to the optic nerve from ... A Successfully Treated Case of Posterior Ischemic Optic Neuropathy that Developed During Antihypertensive Therapy for ... The optic disc is where the axons from the retinal ganglion cells collect into the optic nerve. The optic nerve is the bundle ... between AAION and non-arteritic AION was made to highlight the different etiologies of anterior ischemic optic neuropathy. ...
Optical coherence tomography angiography in acute non-arteritic anterior ischaemic optic neuropathy ... Optical coherence tomography angiography in acute non-arteritic anterior ischaemic optic neuropathy ... Optical coherence tomography angiography in acute non-arteritic anterior ischaemic optic neuropathy ...
It is the most common cause of acute optic neu ... Commonly unilateral, sudden vision loss as a result of optic ... It is the most common cause of acute optic neuropathy in older people. Vision loss is permanent, with the possibility of ... Commonly unilateral, sudden vision loss as a result of optic nerve head swelling. ...
Diff selection: Mark the radio buttons of the revisions to compare and hit enter or the button at the bottom ...
Ischemic Optic Neuropathy - Etiology, pathophysiology, symptoms, signs, diagnosis & prognosis from the MSD Manuals - Medical ... A small optic cup to optic disk ratio is a risk factor for nonarteritic ischemic optic neuropathy but not for the arteritic ... Prognosis for Ischemic Optic Neuropathy There is no effective treatment for the nonarteritic variety of optic nerve infarction ... Ischemic optic neuropathy is infarction of the optic disk. It can be arteritic or nonarteritic. The only constant symptom is ...
The effect of hyperglycaemia on experimental subacute ischaemic optic neuropathy and retinopathy. ... optic neuropathy. hyperglycaemia. ischaemia. Research by Publication. Provenance: Copyright material removed from digital ... In the optic nerve, 2VO caused axonal transport disruption, followed by the loss of axonal cytoskeleton proteins, glial cell ... Thus, at various times after surgery, retinas and optic nerves were removed form RNA or Western blot analysis or to be ...
Ito ay nangyayari kapag ang daloy ng dugo sa optic nerve ng iyong mata ay nagambala, na... ... Ang ischemic optic neuropathy (ION) ay nangyayari kapag ang daloy ng dugo sa optic nerve ng iyong mata ay nagambala, na ... Ang ischemic optic neuropathy (ION) ay maaaring makaapekto sa sinuman, ngunit mas malamang na magkaroon ka nito kung ikaw ay: ... Ang iyong optalmolohista ay magsasagawa ng isang pagsusulit sa mata upang maghanap ng katibayan ng ischemic optic neuropathy ( ...
9. Ischemic Optic Neuropathy Decompression Trial Research Group. Ischemic optic neuropathy decompression trial: twenty-four- ... Keywords: Ischemic optic neuropathy; Neuroprotection; Retinal ganglion cells Introduction. Nonarteritic anterior ischemic optic ... Nonarteritic anterior ischemic optic neuropathy (NAION) is the second most common form of optic neuropathy. Most patients show ... Optic nerve inflammation and demyelination in a rodent model of nonarteritic anterior ischemic optic neuropathy. Invest ...
Exploration of the association of Non-Arteritic Anterior Ischemic Optic Neuropathy (NAION) following air travel. ... "non-arteritic anterior ischemic optic neuropathy", "flight", "high altitude", and "ischemic optic neuropathy". ... Ischemic Optic Neuropathy Decompression Trial Research Group. The fellow eye in NAION: report from the ischemic optic ... Nonarteritic anterior ischemic optic neuropathy in a child with optic disk drusen. J AAPOS. 2012 Apr;16(2):207-9. doi: 10.1016/ ...
Unusual optic disc infarction in a case of arteritic anterior ischaemic optic neuropathy (AAION). Singapore Med J 2015;56:e36- ... Nonarteritic Anterior Ischemic Optic Neuropathy Following COVID-19 Vaccination: A Case Report2022 April;36(2) ... Arteritic anterior ischemic optic neuropathy associated with giant cell arteritis in an elderly Korean man. Korean J Ophthalmol ... Neutrophil to Lymphocyte Ratio in Patients with Nonarteritic Anterior Ischemic Optic Neuropathy2017 April;31(2) ...
We report a case of bilateral postoperative posterior ischemic optic neuropathy. HISTORY AND SIGNS: A previously healthy 51- ... Three mechanisms for posterior ischemic optic neuropathy are recognized: arteritic, non-arteritic, and peri- or postoperative. ... Ophthalmic examination revealed decreased visual acuity to count fingers and normal optic disc without swelling or hemorrhages ... Posterior ischemic optic neuropathy (PION) is a rare cause of bilateral severe and bilateral visual loss. ...
Unusual optic disc infarction in a case of arteritic anterior ischaemic optic neuropathy (AAION). Singapore Med J 2015;56:e36-8 ... 동맥염성 앞허혈시신경병증(arteritic anterior ischemic optic neuropathy)은 거대세포동맥염과 관련된 가장 흔한 안과적 합병증으로 비가역적인 시력저하를 일으킬 수 있는데 이는 시신경유두(optic ... Keywords: Arteritic anterior ischemic optic neuropathy, Giant cell arteritis, Optic disc swelling ... Keywords: Arteritic anterior ischemic optic neuropathy, Giant cell arteritis, Optic disc swelling ...
A nonarteritic anterior ischemic optic neuropathy clinical trial: An industry and NORDIC collaboration. Journal of Neuro- ... A nonarteritic anterior ischemic optic neuropathy clinical trial: An industry and NORDIC collaboration. / Kupersmith, Mark J.; ... A nonarteritic anterior ischemic optic neuropathy clinical trial: An industry and NORDIC collaboration. ... Kupersmith, M. J., & Miller, N. R. (2016). A nonarteritic anterior ischemic optic neuropathy clinical trial: An industry and ...
Nonarteritic anterior ischemic optic neuropathy (NAION) is the most common optic neuropathy of the elderly that causes sudden ... Keywords: : Intravitreal injection, nonarteritic anterior ischemic optic neuropathy, optic coherence tomography, optic nerve, ... Optic disc edema in non-arteritic anterior ischemic optic neuropathy Graefes. Arch Clin Exp Ophthalmol 2007; 245: 1107-21.. ... Zimmerman Optic disc edema in non-arteritic anterior ischemic optic neuropathy Graefes Arch Clin. Exp Ophthalmol 2007; 245: ...
Efficacy and safety of compound anisodine injection for anterior ischemic optic neuropathy: a meta-analysis. July 20, 2022 ... To evaluate the efficacy and safety of compound anisodine (CA) injection for anterior ischemic optic neuropathy (AION). ... Tags: Compound anisodine, Ischemic pptic neuropathy, Meta-analysis, Systematic review, Treatment outcome ...
Anterior Ischemic Optic Neuropathy. *Aphakia and Other Disorders of Lens. *Autoimmune Diseases ...
Macular Evaluation wıth Spectral Domain Type Optic Coherence Tomography in Eyes with Acute Nonarteritic Ischemic Optic ... Characteristics of patients with nonarteritic anterior ischemic optic neuropathy eligible for the Ischemic optic neuropathy ... Acute nonarteritic anterior ischemic optic neuropathy (NAION) is the most common optic neuropathy at the elderly population ... Keywords: Anti-VEGF agents, Macula, Nonarteritic ischemic optic neuropathy, Optic coherence tomography, Ranibizumab, ...
Optic Disc Drusen Studies Consortium. Young Adults with Anterior Ischemic Optic Neuropathy: A Multicenter Optic Disc Drusen ... Ipsilateral Recurrence of Optic Disc Drusen-Associated Anterior Ischemic Optic Neuropathy in a 15-Year-Old Boy. Al-Bakri et al ... Young Adults with Anterior Ischemic Optic Neuropathy: A Multicenter Optic Disc Drusen Study. Hamann et al. American Journal of ... have occasionally been reported in patients with non-arteritic anterior ischemic optic neuropathy (NA-AION). The purpose of ...
A rare vision problem called NAION -- short for "nonarteritic anterior ischemic optic neuropathy" -- has been reported by a few ... The condition causes a sudden loss of eyesight because blood flow is blocked to the optic nerve. People who have a higher ...
What to know about anterior ischemic optic neuropathy. Anterior ischemic optic neuropathy occurs when damage to the optic nerve ...
... control pain signals to a region of the brain promises to open new research avenues for the treatment of peripheral neuropathy. ... Non-arteritic ischemic optic neuropathy (NAION): What to know. NAION is an eye condition that causes sudden-onset, painless ... In diabetic neuropathy - one of the most common forms of peripheral neuropathy - pain can start in the feet then progress up ... Peripheral neuropathy and COVID vaccine: What is the connection?. Rarely, the COVID vaccine may lead to neuropathy symptoms. ...
Ischemic optic neuropathy [non-arteritic anterior ischemic optic neuropathy (NAION)]. H47.091 - H47.099. Other disorders of ... Characteristics of patients with nonarteritic anterior ischemic optic neuropathy eligible for the Ischemic Optic Neuropathy ... Optic Nerve Decompression for Traumatic Optic Neuropathy and Non-Traumatic Compressive Optic Neuropathy. In a retrospective, ... Ischemic Optic Neuropathy Decompression Trial indicate that optic nerve decompression surgery for nonarteritic ischemic optic ...
Ischemic optic neuropathy in sickle cell disease. Am J Ophthalmol. 1988 Feb 15. 105(2):212-3. [QxMD MEDLINE Link]. ...
Ischemic optic neuropathy in sickle cell disease. Am J Ophthalmol. 1988 Feb 15. 105(2):212-3. [QxMD MEDLINE Link]. ...
  • Optic atrophy of varying degrees ensues within the next few weeks as a result of the hypoxic episode and is usually generalized but may be sectorial in NAION. (medscape.com)
  • Early observations of optic disc photographs suggested that patients with congenitally smaller discs and having smaller or nonexistent optic nerve cups have an anatomical predisposition for nonarteritic anterior ischemic optic neuropathy (NAION). (medscape.com)
  • The incidence of nonarteritic anterior ischemic optic neuropathy (NAION) is 2.3-10.3 per 100,000 in the United States, and, for the arteritic type, it is 0.36 per 100,000. (medscape.com)
  • Eligibility criteria for randomization to either optic nerve sheath decompression surgery or careful follow-up included a diagnosis of acute unilateral nonarteritic anterior ischemic optic neuropathy (NAION), a visual acuity of 20/64 or worse and better than no light perception, and an age of 50 years or older. (nih.gov)
  • Recent literature suggests a genetic component for non-arteritic anterior ischemic optic neuropathy (NAION). (molvis.org)
  • Anterior ischemic optic neuropathy (AION) occurs in two forms: arteritic and nonarteritic (NAION). (molvis.org)
  • In contrast, NAION results from the coincidence of cardiovascular risk factors in a patient with "crowded" optic discs. (checkorphan.org)
  • Nonarteritic anterior ischemic optic neuropathy (NAION) is the second most common form of optic neuropathy. (ekjo.org)
  • Nonarteritic anterior ischemic optic neuropathy (NAION) is one of the most common forms of optic neuropathy in adults, with an annual incidence of 2.3 to 10.2 per 100,000 population in the United States [ 1 - 3 ]. (ekjo.org)
  • Few treatment strategies have been proposed, such as optic nerve decompression surgery and steroid, but none of these treatments can provide strong evidence of efficacy to treat NAION eyes [ 8 - 10 ]. (ekjo.org)
  • Considering NAION as one of the most common optic neuropathies, with its unpredictable and often poor prognosis as well as the lack of definitive treatment, studies aimed at finding a therapy for NAION are of high importance. (ekjo.org)
  • Most cases of AION are classified as non-arteritic anterior ischemic optic neuropathy (NAION), which is the most common cause of acute unilateral optic neuropathy in older individuals. (eyewiki.org)
  • NAION is presumed to be due to ischemia of the anterior portion of the optic nerve, but the precise pathophysiology remains controversial. (eyewiki.org)
  • The diagnosis of NAION is usually made clinically, and typical cases present with acute, unilateral, painless loss of vision, optic disc edema, and a relative afferent pupillary defect (RAPD) that leads to optic atrophy within a few weeks [1] . (eyewiki.org)
  • The second mechanism for NAION is through a thromboembolic event, whereby deep vein thrombi embolize and subsequently cause occlusion of the vessels supplying the optic nerve, producing ischemic optic neuropathy [3] . (eyewiki.org)
  • however, in order for a thrombo-embolus to trigger NAION, the formed thrombus must pass through a right-to-left shunt, such as a patent foramen ovale (PFO), to enter the arterial circulation and make its way to the short posterior ciliary vessels that supply the head of the optic nerve. (eyewiki.org)
  • Thus, this treatment trial, which assesses the efficacy and safety of IVT administration of QPI-1007 to avoid the potential complications of systemically administered therapy, could be the first to show optic nerve protection in patients with NAION. (johnshopkins.edu)
  • To evaluate the effect of a single intravitreal ranibizumab injection in eyes with acute nonarteritic ischemic optic neuropathy (NAION). (openophthalmologyjournal.com)
  • To evaluate the macula with spectral domain type optic coherence tomography (OCT) in eyes with acute nonarteritic anterior ischemic optic neuropathy (NAION) at the presentation visit. (openophthalmologyjournal.com)
  • A rare vision problem called NAION -- short for "nonarteritic anterior ischemic optic neuropathy " -- has been reported by a few men using these drugs. (webmd.com)
  • Non-arteritic anterior ischemic optic neuropathy (NAION) is a common cause of sudden loss of vision, especially in the elderly. (aetna.com)
  • There is no direct treatment for NAION, although corticosteroids are sometimes used to reduce optic nerve edema. (aetna.com)
  • Initial results of uncontrolled studies suggested that optic nerve sheath decompression was a promising treatment of progressive visual loss in patients with NAION. (aetna.com)
  • To resolve the controversy over the effectiveness of optic nerve decompression for NAION, the National Eye Institute sponsored the Ischemic Optic Neuropathy Decompression Trial, a multicenter, randomized controlled clinical trial of optic nerve decompression surgery for patients with NAION. (aetna.com)
  • The investigators concluded that optic nerve decompression surgery is not an effective treatment for NAION, and in fact, may increase the risk of progressive visual loss in NAION patients. (aetna.com)
  • A Cochrane review (Dickersin et al, 2012) concluded that results from the single trial indicate no evidence of a beneficial effect of optic nerve decompression surgery for NAION. (aetna.com)
  • A small optic cup to optic disk ratio is a risk factor for nonarteritic ischemic optic neuropathy but not for the arteritic variety. (msdmanuals.com)
  • A structured evidence review (Dickersin and Manheimer, 2002) concluded that "[r]esults from the Ischemic Optic Neuropathy Decompression Trial indicate that optic nerve decompression surgery for nonarteritic ischemic optic neuropathy is not effective. (aetna.com)
  • Anterior ischemic optic neuropathy (AION) is the most common cause of acute optic neuropathy in older age groups. (medscape.com)
  • AION is characterized by visual loss associated with optic disc swelling of a pallid nature, sometimes with flame hemorrhages on the swollen disc or nearby neuroretinal layer, and sometimes with nearby cotton-wool exudates. (medscape.com)
  • Although the pathophysiology differs in the arteritic form of AION, optic nerve ischemia is the common causative factor of both the acute episode and the resultant visual loss. (medscape.com)
  • Anterior ischemic optic neuropathy (AION) is thought to be an ischemic process affecting the posterior circulation of the globe, principally vessels (ie, short posterior ciliary arteries) supplying the optic nerve at its exit from the eye. (medscape.com)
  • This type of structural/ischemic spiral is less implicated in the arteritic type of AION, in which the entire ophthalmic arterial circulation to the eye and orbit may be compromised. (medscape.com)
  • Patients with both arteritic and nonarteritic forms of anterior ischemic optic neuropathy (AION) are usually older than 50 years, with females predominating in the arteritic group. (medscape.com)
  • ION is of two types: anterior (AION) and posterior (PION), the first involving the anterior part of the optic nerve (also called the optic nerve head, ONH) and the second, the rest of the optic nerve. (intechopen.com)
  • AION represents an acute ischemic disorder (a segmental infarction) of the ONH supplied by the posterior ciliary arteries (PCAs), while PION has no specific location in the posterior part of the optic nerve and does not represent ischemia in a specific artery [ 1 ]. (intechopen.com)
  • Anterior ischemic optic neuropathy (AION ) is a medical condition involving loss of vision due to damage to the optic nerve from insufficient blood supply. (checkorphan.org)
  • The distinction between AAION and non-arteritic AION was made to highlight the different etiologies of anterior ischemic optic neuropathy. (checkorphan.org)
  • Anterior ischemic optic neuropathy (AION) can be arteritic (due to giant cell arteritis most commonly) or non-arteritic. (eyewiki.org)
  • To evaluate the efficacy and safety of compound anisodine (CA) injection for anterior ischemic optic neuropathy (AION). (cjeo-journal.org)
  • Optic disc drusen (ODD), present in 2% of the general population, have occasionally been reported in patients with non-arteritic anterior ischemic optic neuropathy (NA-AION). (opticdiscdrusen.com)
  • All patients with NA-AION age 50 years or less, seen in neuro-ophthalmology clinics of the international ODDS (Optic Disc Drusen Studies) Consortium between April 1, 2017, and March 31, 2019, were identified. (opticdiscdrusen.com)
  • Rarely, complications of intraocular surgery or acute blood loss may cause an ischemic event in the optic nerve. (wikipedia.org)
  • It is characterized by acute vision loss without initial disc edema, but with subsequent optic disc atrophy. (wikipedia.org)
  • It is the most common cause of acute optic neuropathy in older people. (eyepatient.net)
  • Orbital MRI with and without contrast, performed with fat saturation sequences, generally reveals enlargement and enhancement of the affected optic nerve in the acute setting. (clevelandclinic.org)
  • VEPs evaluate optic nerve function by calculating P100 latency and amplitude, which are generally abnormal in the setting of acute and remote optic neuritis. (clevelandclinic.org)
  • Traumatic optic neuropathy (TON) refers to an acute injury of the optic nerve secondary to trauma. (medscape.com)
  • In the acute phase, the optic nerve usually appears normal on funduscopic examination, but optic nerve atrophy is often seen 3-6 weeks after the injury. (medscape.com)
  • A secondary mechanism can result in optic nerve swelling after the occurrence the acute injury. (medscape.com)
  • We report a case of papilledema without the typical symptoms of arteritic anterior ischemic optic neuropathy, ultimately diagnosed as a subtype of giant cell arteritis, which has not been reported previously in Korea. (jkos.org)
  • Therefore, the possibility of giant cell arteritis should always be considered with optic disc swelling in both eyes. (jkos.org)
  • Ischemic optic neuropathy (ION) is the loss of structure and function of a portion of the optic nerve due to obstruction of blood flow to the nerve (i.e. ischemia). (wikipedia.org)
  • As a result of understanding that the mechanism for GCA was inflammatory and often not merely localized to optic nerve ischemia, treatment of GCA with steroids was started at the Mayo Clinic in 1949. (medscape.com)
  • More posterior ischemia results in a similar condition, without visible swelling, and is termed posterior ischemic optic neuropathy. (medscape.com)
  • As an ischemic episode evolves, the swelling compromises circulation within a presumable already more compact disc, with a spiral of ischemia and swelling resulting in further neuronal damage. (medscape.com)
  • These vascular risk factors lead to ischemia (poor blood supply) to a portion of the optic disc. (checkorphan.org)
  • The disc then swells, and in a crowded optic disc, this leads to compression and more ischemia. (checkorphan.org)
  • Only glial cells support the optic disc at this site, and it is the only portion of the optic nerve in which swelling can occur. (medscape.com)
  • Commonly unilateral, sudden vision loss as a result of optic nerve head swelling. (eyepatient.net)
  • Most ischemic optic neuropathy is unilateral. (msdmanuals.com)
  • Examination findings usually include decreased visual acuity, a visual field defect, color vision loss, a relative afferent pupillary defect, and a swollen optic nerve head. (wikipedia.org)
  • Afterwards, there was no improvement in visual acuity, and optic nerve atrophy occurred. (jkos.org)
  • Patients with traumatic optic neuropathy (TON) can present with a variable degree of vision loss (decreased visual acuity, visual field abnormalities, or loss of color vision). (medscape.com)
  • Imaging modalities used in the diagnosis of optic neuritis include orbital MRI and optical coherence tomography (OCT). These tools can be particularly helpful if the clinical history or physical examination findings are atypical for ON. (clevelandclinic.org)
  • Ocular ischemic syndrome editor, Cynthia A. Bradford, executive (2004). (wikipedia.org)
  • The pain that occurs with optic neuritis is usually ocular, retroocular, periorbital, or a frontal headache. (clevelandclinic.org)
  • On left side, it leads to Nyctohemeral IOP (with CCT determination) curve within normal range, which then leads to Non-IOP-related optic neuropathy and then to Assessment of the ocular and optic nerve perfusion pressure. (cdc.gov)
  • The pathophysiology of traumatic optic neuropathy (TON) is thought to be multifactorial, and some researchers have also postulated a primary and secondary mechanism of injury. (medscape.com)
  • Every patient underwent clinical examination, the Octopus 900 perimetry in G program, laboratory testing, while the compressive optic neuropathy was rule out with MSCT of the brain and orbits. (srce.hr)
  • Compressive Optic Neuropathy. (slackbooks.com)
  • The optic disc is where the axons from the retinal ganglion cells collect into the optic nerve. (checkorphan.org)
  • Such injury leads to ischemic injury to the retinal ganglion cells within the optic canal. (medscape.com)
  • Optic nerve decompression surgery (also known as optic nerve sheath decompression surgery) involves cutting slits or a window in the optic nerve sheath to allow cerebrospinal fluid to escape, thereby reducing the pressure around the optic nerve. (aetna.com)
  • What are the typical clinical features of optic neuritis? (clevelandclinic.org)
  • Optic neuritis (ON) is a common manifestation of multiple sclerosis (MS), and refers to inflammation of the optic nerve. (clevelandclinic.org)
  • How to approach the patient with suspected optic neuritis? (clevelandclinic.org)
  • Funduscopic examination can appear normal acutely, but disc edema can be present in approximately one-third of patients (particularly those with anterior optic neuritis).1, 2 Optic disc pallor is generally seen weeks to months following onset of typical optic neuritis. (clevelandclinic.org)
  • Prolonged P100 latency is a characteristic of remote optic neuritis. (clevelandclinic.org)
  • What is the neurologic differential diagnosis of optic neuritis? (clevelandclinic.org)
  • 8 ]. Complete blood cell count, erythocyte sedimentation rate and C-reactive protein analysis were obtanined to exclude the arteritic type of anterior ischemic optic neuropathy. (openophthalmologyjournal.com)
  • Typical symptoms are painless impairment of visual function accompanied by relative afferent pupillary defect, edema of the optic disc and visual fi eld defects. (srce.hr)
  • OCT at onset of ON is also potentially confounded by edema of the optic disc, which may lead to overestimates of baseline RNFL.4 Ganglion cell layer (GCL) thickness, another OCT measure, is not confounded by disc edema but declines in a similar time frame to RNFL and therefore may be more useful as a baseline measurement. (clevelandclinic.org)
  • Although there is no recognized treatment that can reverse the visual loss, upon recent reports, optic nerve health decompression may be beneficial for a select group of patients with a gradual decline in vision due to ION. (wikipedia.org)
  • Vidović T, Cerovski B, Perić S, Kordić R, Mrazovac D. Corticosteroid Therapy in Patients with Non-arteritic Anterior Ischemic Optic Neuropathy. (srce.hr)
  • Aim is to present 38 patients with nonarteritic anterior ischemic optic neuropathy who were treated with corticosteroid therapy. (srce.hr)
  • To describe the baseline clinical characteristics of patients in the Ischemic Optic Neuropathy Decompression Trial (IONDT). (nih.gov)
  • In some patients the optic nerve is nearly as large as the opening in the back of the eye, and the optic disc appears "crowded" when seen by ophthalmoscopy. (checkorphan.org)
  • They hope the findings will lead to new research to help patients suffering from peripheral neuropathy or neuropathic pain. (medicalnewstoday.com)
  • Predicting patients' risk of ischemic optic neuropathy after cardiac surgery. (aao.org)
  • The diagnosis was based on the criteria set for the ischemic optic neuropathy decompression trial (presence of visual disturbances, relative afferent pupillary defect, a swollen disc and an appropiate visual field defect. (openophthalmologyjournal.com)
  • Arteritic anterior ischemic optic neuropathy (AAION) is caused by vascular occlusion of the posterior ciliary arteries that supply the optic nerve head (ONH). (ekjo.org)
  • For an uncomplicated retinal vein occlusion, whether it is ischemic or nonischemic, management consists of close monitoring to detect complications and treatment of underlying risk factors. (bmj.com)
  • The optic disk is swollen and elevated, and the swollen nerve fibers obscure the fine surface vessels of the optic nerve. (msdmanuals.com)
  • In peripheral neuropathy, the damaged nerve fibers have a heightened response to normal signals and send incorrect messages to pain centers in the brain - a process known as "peripheral and central sensitization. (medicalnewstoday.com)
  • This is in contrast to direct TON, which results from an anatomical disruption of the optic nerve fibers from penetrating orbital trauma, bone fragments within the optic canal, or nerve sheath hematomas. (medscape.com)
  • With this mechanism, the nerve fibers may be injured against the falciform dural fold or through a shearing force where the nerve becomes fixed as it enters the intracranial opening of the optic foramen. (medscape.com)
  • It is caused by infarction of the short posterior ciliary arteries supplying the anterior optic nerve. (aetna.com)
  • Ischemic optic neuropathy is infarction of the optic disk. (msdmanuals.com)
  • Atherosclerotic narrowing of the posterior ciliary arteries may predispose to nonarteritic optic nerve infarction, particularly after a hypotensive episode. (msdmanuals.com)
  • Vision loss with both varieties of optic nerve infarction is typically rapid (over minutes, hours, or days) and painless. (msdmanuals.com)
  • Diagnosis of optic nerve infarction is based mainly on clinical evaluation, but ancillary testing may be needed. (msdmanuals.com)
  • Magnetic resonance imaging revealed no specific findings, leading to a diagnosis of anterior ischemic optic neuropathy. (jkos.org)
  • Sectorial optic atrophy of the right eye as a late finding resulting from anterior ischemic optic neuropathy. (medscape.com)
  • Field defects typical of ischemic optic neuropathy were probably first described by Knapp in 1875. (medscape.com)
  • In 1924, Uhthoff first described severe visual loss, with field defects and swollen optic discs. (medscape.com)
  • For example, in one of the most common, diabetic neuropathy , nerve damage occurs in an ascending pattern. (medicalnewstoday.com)
  • An indirect injury to the optic nerve typically occurs from the transmission of forces to the optic canal from blunt head trauma. (medscape.com)
  • Kupersmith, MJ & Miller, NR 2016, ' A nonarteritic anterior ischemic optic neuropathy clinical trial: An industry and NORDIC collaboration ', Journal of Neuro-Ophthalmology , vol. 36, no. 3, pp. 235-237. (johnshopkins.edu)
  • The presence of hemorrhages or exudates on funduscopic examination is more suggestive of other, non-demyelinating etiologies of optic neuropathy and warrants ophthalmology evaluation. (clevelandclinic.org)
  • Optic disc swelling and relative afferent pupillary disorder were also evident in the left eye. (jkos.org)
  • Ito ay tinukoy bilang isang pansamantalang atakeng ischemic o transient ischemic attack (TIA). (theyenews.com)
  • moderate to severe VF defect improved in 79% in non-ischemic CRVO and in 27% in ischemic CRVO. (nih.gov)
  • In HCRVO, overall findings demonstrated that initial VA and VF defect and the final visual outcome were different in non-ischemic from ischemic HCRVO - much better in the former than the latter. (nih.gov)
  • The condition causes a sudden loss of eyesight because blood flow is blocked to the optic nerve. (webmd.com)
  • Ischemic forms of optic neuropathy are typically classified as either anterior ischemic optic neuropathy or posterior ischemic optic neuropathy according to the part of the optic nerve that is affected. (wikipedia.org)
  • The optic nerve swelling can exacerbate retinal ganglion cell degeneration by further compromising the vascular blood supply, either through a rise in intraluminal pressure or reactive vasospasm. (medscape.com)
  • Miller, Neil R. / A nonarteritic anterior ischemic optic neuropathy clinical trial : An industry and NORDIC collaboration . (johnshopkins.edu)
  • Over a few days, optic disc edema develops, sometimes associated with flame hemorrhages of the swollen disc or nearby cotton-wool exudates. (molvis.org)
  • The first is a predisposition in the form of a type of optic disc shape. (checkorphan.org)
  • Fluorescein angiography revealed delayed filling of the optic disc and adjacent choroid in both eyes. (ekjo.org)
  • Diamox, Lasix, corticosteroids), and disc swelling with visual field loss progresses, direct fenestration of the optic nerve sheaths via medial or lateral orbitotomy has been shown to be an effective and relatively simple procedure for relief of papilledema. (aetna.com)
  • Specifically, the aim of the project was to test the hypothesis that elevated blood and vitreal glucose levels induced by short-term diabetes would attenuate prolonged ischaemic retinal degeneration in the rat. (edu.au)
  • The image below depicts traumatic optic neuropathy. (medscape.com)