Optic Nerve Neoplasms
Optic Nerve
Cranial Nerve Neoplasms
Optic Nerve Injuries
Optic Disk
Optic Nerve Diseases
Optic Neuritis
Optic Chiasm
Optic Atrophy
Retinal Ganglion Cells
Nerve Fibers
Sciatic Nerve
Optic Nerve Glioma
Peripheral Nerves
Optic Neuropathy, Ischemic
Retina
Glaucoma
Papilledema
Optic Lobe, Nonmammalian
Optic Atrophies, Hereditary
Arachnoid Cysts
Encyclopedias as Topic
Nervous System Neoplasms
Peripheral Nervous System Neoplasms
Nerve Sheath Neoplasms
Arachnoid
Neurological complications of neurofibromatosis type 1 in adulthood. (1/69)
Neurofibromatosis type 1 (NF1) is a genetic disease with a wide range of neurological manifestations. To examine these, and to evaluate neurological morbidity in adulthood of patients with NF1, we studied a hospital-based series of 158 patients that included 138 adult patients aged >18 years and 20 children. NF1 evaluation included a multidisciplinary clinical and a clinically oriented radiological investigation. Neurological events occurring during childhood (in both children and adults of the series) and adulthood were recorded. One or several neurological manifestations have been observed in 55% of patients (adults and children) (n = 87). These included: headache (28 patients); hydrocephalus (7); epilepsy (5); lacunar stroke (1); white matter disease (1); intraspinal neurofibroma (3); facial palsy (1); radiculopathy (5); and polyneuropathy (2). Tumours included: optic pathway tumours (20); meningioma (2); cerebral glioma (3); and malignant peripheral nerve sheath tumours (6). Life-threatening complications were observed in five adults and included four malignant peripheral nerve sheath tumours and one meningioma. Pain was the leading symptom in 11 adults and was related to malignant peripheral nerve sheath tumours, complications of intraspinal neurofibromas, subcutaneous neurofibromas and peripheral nerve neurofibromas. NF1 in adults was not associated with other disabling or life-threatening neurological complications. Symptomatic optic pathway tumours, cerebral gliomas, symptomatic aqueductal stenosis and spinal compression due to intraspinal NF were observed exclusively during childhood. In this series, the predominant neurological features of adults with NF1 were chronic pain and malignant peripheral nerve sheath tumours. (+info)Ganglioglioma of the optic chiasm: case report and review of the literature. (2/69)
We report a case of a hypothalamic chiasmatic ganglioglioma in a 21-year-old woman who presented with hyperprolactinemia and developed visual field defects. This circumscribed cystic lesion with an enhancing mural nodule was radiologically indistinguishable from a pilocytic astrocytoma. Although rare, gangliogliomas should be included in the differential diagnosis of lesions occurring in this area of the brain. (+info)Carboplatin is effective therapy for young children with progressive optic pathway tumors: a Pediatric Oncology Group phase II study. (3/69)
The Pediatric Oncology Group conducted a phase II study to evaluate the activity of carboplatin in children 5 years or younger with progressive optic pathway tumors (OPTs). Of the 51 patients accrued to this study, 1 was not eligible because the child was older than 6 years. Fifty patients were eligible and had either neuro-imaging or symptomatic evidence of progressive OPTs. Twenty-one of 50 had evidence of neurofibromatosis type I (NF-1). Therapy consisted of carboplatin 560 mg/m2 at 4-week intervals. Patients with stable disease or better after two courses were continued on therapy for 18 months or until progressive disease. Of the 50 eligible children, 39 had stable disease or better, and 34 completed the 18-month therapy. Our data are sufficient to conclude that the proportion of objective responses (complete, partial, or minor response or stable disease) exceeded 30% (P < 0.00001), and the approximate 95% confidence interval estimate of the objective response rate was 0.665 to 0.895. Twenty-one patients went off protocol because of progressive disease. Fifteen patients progressed during the 18-month therapy, and 6 patients progressed after completing therapy. Six children died with progressive disease. Major toxicities were neutropenia and thrombocytopenia, and 3 children experienced allergic reactions. Carboplatin is active and safe for the treatment of young children with progressive OPTs. The addition of other potentially active drugs may further increase the event-free survival for these children. (+info)Patients with persistent pain after enucleation studied by MRI dynamic color mapping and histopathology. (4/69)
PURPOSE: To study possible causes of persistent pain in patients who underwent enucleation of the globe and in whom all other noninvasively detectable causes of pain had been ruled out. METHODS: Twenty patients were studied, 10 with intractable pain (score >5 on a 0-to-9 self-reporting pain scale) persisting for more than 6 months after enucleation (for various reasons) and 10 without pain (score <4) at least 6 months after enucleation. Magnetic resonance imaging (MRI) with dynamic color mapping (MRI-DCM) was used to quantify the motion of the optic nerve in millimeters per degree of gaze, 2 to 3 mm behind the implant. Histopathologic study of biopsy specimens was used to verify imaging findings. RESULTS: The optic nerve was attached to the implant in almost all (19/20) patients. On average, the motion was significantly less in patients with persistent intractable pain (0.04 mm/deg) than in patients without pain (0.08 mm/deg; normal orbit, 0.13 mm/deg). A biopsy specimen was available in 5 of 10 patients with persistent pain, and in 4 of those 5, microscopic neuroma was found close to the optic nerve-implant junction. CONCLUSIONS: In the enucleated orbit, the optic nerve is usually attached to the implant and soft tissue motion is decreased. In patients who have persistent pain after enucleation, motion is decreased even more, and a high percentage of microscopic amputation neuromas are found. Increased stiffness of orbital soft tissue and optic nerve attachment after enucleation are detectable using MRI-DCM, and may play a role in susceptible patients in the development of microscopic amputation neuroma and pain. (+info)Brain tumors in children with neurofibromatosis: additional neuropsychological morbidity? (5/69)
Neurofibromatosis type 1 is a common autosomal dominant genetic disorder associated with numerous physical anomalies and an increased incidence of neuropsychological impairment. Tumors of the CNS occur in approximately 15% of children with neurofibromatosis, presenting additional risk for cognitive impairment. This study examines the impact of an additional diagnosis of brain tumor on the cognitive profile of children with neurofibromatosis. A comprehensive battery of neuropsychological tests was administered to 149 children with neurofibromatosis. Thirty-six of these children had a codiagnosis of brain tumor. A subset of 36 children with neurofibromatosis alone was matched with the group of children diagnosed with neurofibromatosis and brain tumor. Although mean scores of the neurofibromatosis plus brain tumor group were, in general, lower than those of the neurofibromatosis alone group, these differences were not statistically significant. Children in the neurofibromatosis plus brain tumor group who received cranial irradiation (n = 9) demonstrated weaker academic abilities than did children with brain tumor who had not received that treatment. These results suggest that neurofibromatosis is associated with impairments in cognitive functioning, but the severity of the problems is not significantly exacerbated by the codiagnosis of a brain tumor unless treatment includes cranial irradiation. (+info)Necrotizing neurosarcoidosis masquerading as a left optic nerve meningioma: case report. (6/69)
Isolated neurosarcoidosis involving the optic nerve meninges is extremely rare and is often indistinguishable from a meningioma in its anatomic site and MR imaging presentation. Characteristic findings include enhanced perineural encasement and thickening of the affected optic nerve on contrast-enhanced T1-weighted cranial MR imaging studies. We present the case report of a patient with isolated necrotizing neurosarcoidosis of the left optic nerve, with clinical and MR imaging findings strongly suggestive of a preoperative diagnosis of a meningioma. (+info)Loss of heterozygosity for the NF2 gene in retinal and optic nerve lesions of patients with neurofibromatosis 2. (7/69)
Individuals affected with the neurofibromatosis 2 (NF2) cancer predisposition syndrome develop specific ocular lesions. To determine whether these lesions result from altered NF2 gene expression, microdissection and PCR were used to investigate 40 ocular lesions from seven eyes of four NF2 patients for LOH, with markers that flank the NF2 gene on chromosome 22q. NF2 protein (merlin) expression was also evaluated in these lesions, using immunohistochemistry. Retinal hamartoma was observed in all seven eyes, including one with combined pigment epithelial and retinal hamartoma (CPERH). Retinal tufts were present in four eyes (three patients), retinal dysplasia in two eyes (two patients), optic nerve neurofibroma in one eye, iris naevoid hyperplasia in two eyes (two patients) and pseudophakia in all eyes. Markers were informative in three patients (six eyes from three unrelated families). One patient was non-informative due to prolonged decalcification. All retinal and optic nerve, but not iris lesions, demonstrated consistent LOH for the NF2 gene. Merlin was not expressed in the retina, optic nerve, or iris lesions. These results suggest that inactivation of the NF2 gene is associated with the formation of a variety of retinal and optic nerve lesions in NF2 patients. (+info)Stereotactic fractionated irradiation of optic nerve sheath meningioma: a new treatment alternative. (8/69)
BACKGROUND: Primary optic nerve sheath meningioma (ONSM) is a rare but almost invariably blinding tumour when its natural history is observed in a "wait and see" strategy. Surgery has hitherto only been advocated in case of progressive disease involving intracranial structures, as it leads to iatrogenic blindness in the overwhelming majority of cases. Therefore, treatment options bearing lesser risk of functional deterioration are highly desirable, both in cases of intracranial involvement as well as during earlier phases of the disease which are currently generally left untreated. The authors report the outcome of the largest series of patients to date treated by stereotactic fractionated irradiation as a new treatment approach in ONSM at all stages. METHODS: 15 patients (16 nerves) underwent stereotactic fractionated conformal irradiation with a total dose of 54 Gy, using standard fractionation. Main outcome parameters included visual acuity and visual field, as well as three dimensional remission as documented by imaging. RESULTS: Tumour control was confirmed in all 15 patients undergoing stereotactic fractionated conformal irradiation (mean follow up 37 (range 12-71) months). No patient developed functional deterioration during or after treatment. Moreover, visual acuity improved by more than two lines in one patient and the visual field improved in six cases. Visual outcome in the other patients remained unchanged. There were no significant side effects of radiation therapy. CONCLUSION: These data provide convincing evidence that stereotactic fractionated conformal irradiation is an effective treatment option for primary ONSM with minimal treatment related morbidity. It should therefore be considered as therapeutic option both in early stage ONSM where surgery cannot be justified as well as in later stages, where surgery is so far considered the first line approach. (+info)Optic nerve neoplasms refer to abnormal growths or tumors that develop within or near the optic nerve. These tumors can be benign (non-cancerous) or malignant (cancerous).
Benign optic nerve neoplasms include optic nerve meningiomas and schwannomas, which originate from the sheaths surrounding the optic nerve. They usually grow slowly and may not cause significant vision loss, but they can lead to compression of the optic nerve, resulting in visual field defects or optic disc swelling (papilledema).
Malignant optic nerve neoplasms are rare but more aggressive. The most common type is optic nerve glioma, which arises from the glial cells within the optic nerve. These tumors can quickly damage the optic nerve and cause severe vision loss.
It's important to note that any optic nerve neoplasm requires prompt medical evaluation and treatment, as they can potentially lead to significant visual impairment or even blindness if left untreated.
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.
Cranial nerve neoplasms refer to abnormal growths or tumors that develop within or near the cranial nerves. These nerves are responsible for transmitting sensory and motor information between the brain and various parts of the head, neck, and trunk. There are 12 pairs of cranial nerves, each with a specific function and location in the skull.
Cranial nerve neoplasms can be benign or malignant and may arise from the nerve itself (schwannoma, neurofibroma) or from surrounding tissues that invade the nerve (meningioma, epidermoid cyst). The growth of these tumors can cause various symptoms depending on their size, location, and rate of growth. Common symptoms include:
* Facial weakness or numbness
* Double vision or other visual disturbances
* Hearing loss or tinnitus (ringing in the ears)
* Difficulty swallowing or speaking
* Loss of smell or taste
* Uncontrollable eye movements or drooping eyelids
Treatment for cranial nerve neoplasms depends on several factors, including the type, size, location, and extent of the tumor, as well as the patient's overall health. Treatment options may include surgery, radiation therapy, chemotherapy, or a combination of these approaches. Regular follow-up care is essential to monitor for recurrence or complications.
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.
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 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.
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.
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.
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.
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.
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.
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.
A nerve crush injury is a type of peripheral nerve injury that occurs when there is excessive pressure or compression applied to a nerve, causing it to become damaged or dysfunctional. This can happen due to various reasons such as trauma from accidents, surgical errors, or prolonged pressure on the nerve from tight casts, clothing, or positions.
The compression disrupts the normal functioning of the nerve, leading to symptoms such as numbness, tingling, weakness, or pain in the affected area. In severe cases, a nerve crush injury can cause permanent damage to the nerve, leading to long-term disability or loss of function. Treatment for nerve crush injuries typically involves relieving the pressure on the nerve, providing supportive care, and in some cases, surgical intervention may be necessary to repair the damaged nerve.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
An Arachnoid cyst is a type of abnormal fluid-filled sac that develops between the brain or spinal cord and the arachnoid membrane, which is one of the three layers that cover and protect the central nervous system. These cysts are filled with cerebrospinal fluid (CSF), which is the same fluid that surrounds and cushions the brain and spinal cord.
Arachnoid cysts can vary in size and may be present at birth or develop later in life due to trauma, infection, or other factors. While many arachnoid cysts are asymptomatic and do not cause any problems, larger cysts or those that grow or shift over time can put pressure on the brain or spinal cord, leading to a range of neurological symptoms such as headaches, seizures, hearing or vision changes, balance or coordination difficulties, and cognitive impairments.
Treatment for arachnoid cysts depends on their size, location, and associated symptoms. In some cases, observation and monitoring may be sufficient, while in others, surgical intervention may be necessary to drain the cyst or create a connection between it and the surrounding CSF space to relieve pressure.
An encyclopedia is a comprehensive reference work containing articles on various topics, usually arranged in alphabetical order. In the context of medicine, a medical encyclopedia is a collection of articles that provide information about a wide range of medical topics, including diseases and conditions, treatments, tests, procedures, and anatomy and physiology. Medical encyclopedias may be published in print or electronic formats and are often used as a starting point for researching medical topics. They can provide reliable and accurate information on medical subjects, making them useful resources for healthcare professionals, students, and patients alike. Some well-known examples of medical encyclopedias include the Merck Manual and the Stedman's Medical Dictionary.
Nervous system neoplasms are abnormal growths or tumors that occur within the nervous system, which includes the brain, spinal cord, and peripheral nerves. These tumors can be benign (non-cancerous) or malignant (cancerous), and their growth can compress or infiltrate surrounding tissues, leading to various neurological symptoms. The causes of nervous system neoplasms are not fully understood but may involve genetic factors, exposure to certain chemicals or radiation, and certain viral infections. Treatment options depend on the type, location, and size of the tumor and can include surgery, radiation therapy, chemotherapy, or a combination of these approaches.
Peripheral nervous system (PNS) neoplasms refer to tumors that originate in the peripheral nerves, which are the nerves outside the brain and spinal cord. These tumors can be benign or malignant (cancerous). Benign tumors, such as schwannomas and neurofibromas, grow slowly and do not spread to other parts of the body. Malignant tumors, such as malignant peripheral nerve sheath tumors (MPNSTs), can invade nearby tissues and may metastasize (spread) to other organs.
PNS neoplasms can cause various symptoms depending on their location and size. Common symptoms include pain, weakness, numbness, or tingling in the affected area. In some cases, PNS neoplasms may not cause any symptoms until they become quite large. Treatment options for PNS neoplasms depend on several factors, including the type, size, and location of the tumor, as well as the patient's overall health. Treatment options may include surgery, radiation therapy, chemotherapy, or a combination of these approaches.
Nerve sheath neoplasms are a group of tumors that arise from the cells surrounding and supporting the nerves. These tumors can be benign or malignant and include schwannomas, neurofibromas, and malignant peripheral nerve sheath tumors (MPNSTs). Schwannomas develop from the Schwann cells that produce the myelin sheath of the nerve, while neurofibromas arise from the nerve's supporting cells called fibroblasts. MPNSTs are cancerous tumors that can grow rapidly and invade surrounding tissues. Nerve sheath neoplasms can cause various symptoms depending on their location and size, including pain, numbness, weakness, or paralysis in the affected area.
The arachnoid is one of the three membranes that cover the brain and the spinal cord, known as the meninges. It is located between the dura mater (the outermost layer) and the pia mater (the innermost layer). The arachnoid is a thin, delicate membrane that is filled with cerebrospinal fluid, which provides protection and nutrition to the central nervous system.
The arachnoid has a spider-web like appearance, hence its name, and it is composed of several layers of collagen fibers and elastic tissue. It is highly vascularized, meaning that it contains many blood vessels, and it plays an important role in regulating the flow of cerebrospinal fluid around the brain and spinal cord.
In some cases, the arachnoid can become inflamed or irritated, leading to a condition called arachnoiditis. This can cause a range of symptoms, including pain, muscle weakness, and sensory changes, and it may require medical treatment to manage.
Central nervous system (CNS) neoplasms refer to a group of abnormal growths or tumors that develop within the brain or spinal cord. These tumors can be benign or malignant, and their growth can compress or disrupt the normal functioning of surrounding brain or spinal cord tissue.
Benign CNS neoplasms are slow-growing and rarely spread to other parts of the body. However, they can still cause significant problems if they grow large enough to put pressure on vital structures within the brain or spinal cord. Malignant CNS neoplasms, on the other hand, are aggressive tumors that can invade and destroy surrounding tissue. They may also spread to other parts of the CNS or, rarely, to other organs in the body.
CNS neoplasms can arise from various types of cells within the brain or spinal cord, including nerve cells, glial cells (which provide support and insulation for nerve cells), and supportive tissues such as blood vessels. The specific type of CNS neoplasm is often used to help guide treatment decisions and determine prognosis.
Symptoms of CNS neoplasms can vary widely depending on the location and size of the tumor, but may include headaches, seizures, weakness or paralysis, vision or hearing changes, balance problems, memory loss, and changes in behavior or personality. Treatment options for CNS neoplasms may include surgery, radiation therapy, chemotherapy, or a combination of these approaches.
Nervous system neoplasm
Cavernous hemangioma
Eye neoplasm
List of MeSH codes (C10)
Orbit (anatomy)
André Rochon-Duvigneaud
List of MeSH codes (C04)
Pilocytic astrocytoma
List of diseases (P)
Diktyoma
Neurofibromin 1
List of MeSH codes (C11)
Tumefactive multiple sclerosis
Hamartoma
Proton therapy
Astroblastoma
Idiopathic orbital inflammatory disease
Pituitary adenoma
Fundus photography
Visual impairment
List of cancer types
Brain tumor
List of MeSH codes (C21)
Retinoblastoma
Meningioma
International Classification of Headache Disorders
List of diseases (G)
List of diseases (S)
Melanocytoma
List of ICD-9 codes 800-999: injury and poisoning
Glioma12
- The second patient was a child with neurofibromatosis type 1 who developed a pigmented peripapillary lesion following excision of an optic nerve glioma. (nih.gov)
- Optic nerve glioma (also known as optic pathway glioma) is the most common primary neoplasm of the optic nerve. (medscape.com)
- A low-grade form of this neoplasm, benign optic glioma, occurs most often in pediatric patients. (medscape.com)
- Axial T2-weighted MRI in a 46-year-old man demonstrates a mass in the lateral geniculate nucleus of the thalamus resulting from contiguous extension of the patient's known optic nerve glioma. (medscape.com)
- Contrasted computed tomography (CT) scanning can be used to characterize local involvement of optic nerve glioma within the orbit. (medscape.com)
- MRI, however, is the preferred method for definitive evaluation of optic nerve glioma. (medscape.com)
- CT scanning is the better modality for identifying uncommon meningioma with flecks of calcification, which are rare in optic nerve glioma. (medscape.com)
- Peripheral and central nervous system neoplasms occur frequently, especially OPTIC NERVE GLIOMA and NEUROFIBROSARCOMA. (edu.au)
- In distinction, an individual is diagnosed to have neurofibromatosis 2 if the person has bilateral eighth nerve masses seen with appropriate imaging techniques or a first degree relative with neurofibromatosis 2 and either: (1) a unilateral eighth nerve mass, (2) Two or more of the following: neurofibroma, meningioma, glioma, schwannoma, or juvenile posterior subcapsular lenticular opacity. (medlink.com)
- A glioma originating in the optic nerve or optic chiasm. (nih.gov)
- These tumors include plexiform neurofibroma, malignant peripheral nerve sheath tumor, optic track glioma, juvenile myelomonocytic leukemia, and subsequent malignant neoplasms caused by prior exposure to mutagenic chemotherapy and/or radiation. (jhu.edu)
- The main differential diagnoses include an immature teratoma and an optic nerve glioma in cases 1 and 2, respectively. (houstonmethodist.org)
Chiasm5
- The diagnosis may be made with a high degree of confidence when the lesion involves the optic chiasm and retrochiasmatic optic pathway. (medscape.com)
- Neoplasms of the hypothalamus frequently originate from adjacent structures, including the OPTIC CHIASM , optic nerve (see OPTIC NERVE NEOPLASMS ), and pituitary gland (see PITUITARY NEOPLASMS ). (nih.gov)
- Pituitary tumors may compress adjacent structures, including the HYPOTHALAMUS, several CRANIAL NERVES, and the OPTIC CHIASM. (embl.de)
- Enhancement of the optic nerves or chiasm after gadolinium injection is a consistent finding, and swelling may also be present. (jamanetwork.com)
- 1 , 2 In the following case, MRI signs of radiation injury to the optic chiasm were demonstrable several months before the vision became impaired. (jamanetwork.com)
Tumors7
- Optic pathway gliomas are benign tumors that are classified as pilocytic astrocytomas . (medscape.com)
- They constitute 50% of primary optic nerve tumors and 1.5-4% of all orbital tumors. (medscape.com)
- However, over time, the growth of these tumors can cause compression on the optic nerve and adjacent blood vessels and muscles severely impacting vision. (myhoustonsurgeons.com)
- Less common but potentially more serious manifestations include optic nerve and other central nervous system gliomas, malignant peripheral nerve sheath tumors, scoliosis, tibial dysplasia, vasculopathy, and gastrointestinal, endocrine, or pulmonary disease. (nih.gov)
- Pituitary gland neoplasms and tumors arising from cranial nerves are considered secondary brain tumors. (vin.com)
- It is the most common primary intracranial neoplasm and the most diversified in histologic patterns among all primary tumors of the CNS. (medscape.com)
- Meningiomas , as defined by the World Health Organization (WHO), are "meningothelial (arachnoid) cell neoplasms, typically attached to the inner surface of the dura mater," and these tumors fall into WHO grades I, II, and III. (medscape.com)
Benign neoplasm1
- Discussion Orbital SFT is a generally benign neoplasm originating from the mesenchyme, uncommon in the orbit. (scitechnol.com)
Treatment of optic neuritis2
- Emerging concepts in the treatment of optic neuritis: mesenchymal stem cell-derived extracellular vesicles. (uchicago.edu)
- Similarly, there has been a substantial change in the treatment of optic neuritis which was earlier limited to steroids and interferons. (lww.com)
Clinical3
- 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)
- 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. (uchicago.edu)
- Antiaquaporin4 antibodies and antimyelin oligodendrocytes antibodies are now considered as distinct entities of optic neuritis with their specific clinical presentation, neuroimaging characteristics, treatment options, and course of the disease. (lww.com)
Neuritis13
- False-positive results can occur because of unilateral optic nerve enhancement or other unilateral disorders, such as optic meningioma, vascular lesions, neuritis, pseudotumor, and sarcoidosis. (medscape.com)
- Optic Neuritis" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (uchicago.edu)
- 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). (uchicago.edu)
- This graph shows the total number of publications written about "Optic Neuritis" by people in this website by year, and whether "Optic Neuritis" was a major or minor topic of these publications. (uchicago.edu)
- Below are the most recent publications written about "Optic Neuritis" by people in Profiles. (uchicago.edu)
- Functional loss in the magnocellular and parvocellular pathways in patients with optic neuritis. (uchicago.edu)
- Histocompatibility types and measles antibodies in multiple sclerosis and optic neuritis. (uchicago.edu)
- Association of parainfluenza antibodies and histocompatibility types in MS and optic neuritis. (uchicago.edu)
- Over the past few years, there has been remarkable development in the area of optic neuritis. (lww.com)
- The development of new immunosuppressant drugs and monoclonal antibodies has reduced the relapses and improved the prognosis of optic neuritis as well as an associated systemic disease. (lww.com)
- This review article tends to provide an update on the approach and management of optic neuritis. (lww.com)
- The landscape of optic neuritis (ON) is rapidly changing with the discovery of new antibodies, advent of latest investigations, and revised diagnostic criteria. (lww.com)
- We searched PubMed and Medline for studies published during the last 10 years with the general term "optic neuritis" and specific terms like "typical optic neuritis," "atypical optic neuritis," "multiple sclerosis," "neuromyelitis optic neuritis," and "myelin oligodendrocyte glycoprotein antibody. (lww.com)
Meningioma1
- Cerebral meningioma is the most frequently reported primary brain tumor of cats and accounts for almost 10% of all nonhematopoietic neoplasms. (vin.com)
Ischemic optic neur3
- Non-arteritic anterior ischemic optic neuropathy (NAION) is a common cause of sudden loss of vision, especially in the elderly. (aetna.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)
- Haemodilution and head-down tilting induce functional injury in the rat optic nerve: A model for peri-operative ischemic optic neuropathy. (uchicago.edu)
Spinal cord1
- A benign or malignant neoplasm that arises from the brain or the spinal cord. (beds.ac.uk)
Ocular1
- We have studied the transgenic mouse strain, Tyrp-1-TAg, to try to gain insight into possible molecular mechanisms common to pigmented ocular neoplasms occurring spontaneously in the eyes of these mice and human choroidal melanoma. (molvis.org)
Sheath2
- 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)
- 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)
Anterior optic1
- It is caused by infarction of the short posterior ciliary arteries supplying the anterior optic nerve. (aetna.com)
Disease1
- Massive choroidal invasion (≥3 mm of invasion), extrascleral extension, or postlaminar optic nerve disease increase the risk that metastatic disease could develop. (aao.org)
Cranial nerve2
- Cranial nerve function was fully intact, and neurological examination findings were normal. (contemporarypediatrics.com)
- Neoplasms involving the brain stem may result in cranial nerve deficits. (vin.com)
Neurofibromatosis1
- Neurofibromatosis 1 is an autosomally dominated inherited genetic condition that predisposes those involved to the development of intracranial neoplasms. (medlink.com)
Diseases1
- 2 3 4 5 6 ] However, a more recent population-based survey conducted in urban Mangalore has shown a prevalence of 8.3/100,000 for MS and 2.6/100,000 for neuromyelitis optic spectrum diseases (NMOSD). (lww.com)
Medulloepithelioma2
Tumor3
- A nervous system neoplasm is a tumor affecting the nervous system. (wikipedia.org)
- For orbital neoplasms that are medial to the optic nerve we can safely perform transnasal minimally invasive endoscopic orbital tumor resection . (myhoustonsurgeons.com)
- The main risk factor associated with death is extraocular extension of the tumor, either directly through the sclera or, more commonly, by invasion of the optic nerve, especially to the surgically resected margin (see Chapter 11, Fig 11-46). (aao.org)
Retina1
- caused by damage to the optic nerve or retina, often leading to increased intraocular pressure. (animalwised.com)
Neuropathies1
- A review of optic neuropathies. (uchicago.edu)
Medial1
- 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)
Retinal1
- Retinal and optic nerve complications in a high dose irradiat. (iaea.org)
Pathways1
- Visual deficits may accompany masses that involve the visual pathways from the occipital lobe of the cerebrum to the optic nerve. (vin.com)
Meningiomas1
- Meningiomas , as defined by the 2016 World Health Organization (WHO), are "a group of mostly benign, slow-growing neoplasms that most likely derive from the meningothelial cells of the arachnoid layer. (medscape.com)
Orbital1
- Solitary fibrous tumour (SFT) is an uncommon neoplasm at the orbital level that behaves in benign way in most cases [ 1 ]. (scitechnol.com)
Lesions1
- [ 9 , 10 ] Although MRI may reveal even subtle lesions of the optic nerve, CT scanning can detect a subtle erosion or expansion of the optic canal. (medscape.com)
Pathway1
- Visual loss from injury to the anterior visual pathway is an important if uncommon complication of radiation treatment for intracranial and paranasal sinus neoplasms. (jamanetwork.com)