Papilledema
Pseudotumor Cerebri
Intracranial Hypertension
Optic Disk
Intracranial Pressure
Headache
Transverse Sinuses
Vision Disorders
Optic Neuropathy, Ischemic
Photography
Bruch Membrane
Flicker Fusion
Optic Atrophy
Optic Nerve
Cerebrospinal Fluid Pressure
Tomography
Subarachnoid Space
Optic Neuritis
Echo-Planar Imaging
Nerve Fibers
Ophthalmoscopic abnormalities in adults with falciparum malaria. (1/183)
We studied 424 adults with falciparum malaria admitted over 28 months. They were divided into three groups: cerebral malaria (n = 214); severe non-cerebral malaria (n = 58); and uncomplicated malaria (n = 152). Fundus examination was done daily from admission to discharge, and weekly thereafter in those with persistent changes. All patients were treated by a protocol based on WHO guidelines. Ophthalmoscopic abnormalities were: retinal haemorrhages, 40 (9.43%) (25 cerebral malaria, 10 severe non-cerebral and five uncomplicated malaria); papilloedema, 17 (7.94%) cerebral malaria and two uncomplicated malaria; blurring of disc margins, 25 (11.68%) cerebral and seven non-cerebral; retinal oedema, six (2.80%) cerebral and five non-cerebral malaria; disc pallor, five patients all with cerebral malaria; vitreous haemorrhage and hard exudate in one patient each, both cerebral malaria. Retinal haemorrhage was associated with cerebral malaria and severe non-cerebral malaria, especially with severe anaemia (p < 0.001), as compared to uncomplicated malaria (p < 0.01). The association of papilloedema and cerebral malaria was highly significant compared to severe non-cerebral malaria (p < 0.001). None of these findings was associated with statistically significant mortality, except disc pallor in cerebral malaria (p < 0.05). (+info)Unilateral papilledema after bone marrow transplantation. (2/183)
We describe a patient who developed unilateral papilledema after allogeneic BMT. This is a rare manifestation of pseudotumor cerebri, which results from elevated intracranial pressure caused by cyclosporin A. The papilledema usually involves the fundi bilaterally, but unilateral involvement has been described. Congenital anomalies, compression and adhesion of the optic nerve sheath are its causes. In this patient, the right optic fundus was spared although leukemic infiltration was present on this side and high-dose irradiation (72 Gy) was given. Although papilledema is a sensitive marker of elevated intracranial pressure, this sign may be masked by constriction of the optic sheath in patients who suffer from leukemic infiltration of the central nervous system and receive high doses of cranial irradiation. (+info)Choroidal folds and papilloedema. (3/183)
AIMS: To assess the clinical and fluorescein angiographic features of choroidal folds seen in association with papilloedema. METHODS: In a retrospective study, the clinical data from a database on patients with choroidal folds (1963-97), including fundus photography and fluorescein angiography, from 32 patients (64 eyes) with choroidal folds in association with papilloedema were reviewed. The clinical and fluorescein angiographic features and the clinical course of choroidal folds in these patients are described. RESULTS: 32 patients had choroidal folds associated with papilloedema. Folds of two distinct categories were observed, either coarse folds or wrinkles. The folds persisted in all cases, even after resolution of papilloedema. Follow up ranged from 1 month to 20 years. Only one patient suffered permanent visual impairment as a result of a choroidal fold. CONCLUSIONS: Choroidal folds exist in two forms, coarse folds and wrinkles. They persist even after papilloedema has resolved. Final visual acuity did not appear to be affected by the presence of choroidal folds in the majority of patients. (+info)Optic disc and retinal microvasculopathy after high-dose chemotherapy and autologous hematopoietic progenitor cell support. (4/183)
The purpose of this study was to prospectively evaluate the retinal and optic nerve changes in patients undergoing high-dose chemotherapy (HDC) followed by autologous hematopoietic progenitor cell support (AHPCS). One hundred and forty patients undergoing HDC and AHPCS underwent extensive pre- and post-transplant ophthalmologic evaluations for development of retinal microvascular complications. One hundred and ten patients received high-dose cyclophosphamide, cisplatin and BCNU; thirty received identical doses of cyclophosphamide and cisplatin, but received paclitaxel instead of BCNU. Thirty-four patients (24%) had retinal findings of either cotton wool spots (CWS) (n = 20) or retinal hemorrhages (n = 18) during follow-up, which ranged from 1 to 12 months. Ten (7%) of these patients, all of whom received BCNU, showed ocular toxicity characterized by CWS 1 to 4 months post transplant (n = 10); optic disc edema (n = 3); and variable vision loss associated with the onset of BCNU-induced pulmonary toxicity. Retinal and optic disc microvascular complications may occur after high-dose chemotherapy followed by AHPCS. The association of ischemic retinal lesions and/or optic disc edema with BCNU-induced pulmonary toxicity and the lack of ocular toxicity in patients that did not receive BCNU may suggest that BCNU is the etiologic agent. (+info)Ultrasonographic evaluation of optic disc swelling: comparison with CSLO in idiopathic intracranial hypertension. (5/183)
PURPOSE: To determine the accuracy and reproducibility of ultrasonographic (US) readings of optic disc elevations in patients with papilledema compared with confocal scanning laser ophthalmoscope (CSLO) measurements. METHODS: One randomly selected eye of 22 patients with idiopathic intracranial hypertension (IIH) and a variable degree of optic disc swelling underwent five and three repeated measurements of disc height using high-resolution ultrasonography (Biovision unit; Quantel Medical, Clermont-Ferrand, France) and CSLO (Heidelberg Retina Tomograph [HRT]; Heidelberg Engineering, Heidelberg, Germany), respectively. The same procedure was assessed in 14 subjects with variable degrees of physiologic optic disc cupping. US and HRT measurements from each group were individually compared with each other to estimate the accuracy of US readings in both disc conditions in comparison with HRT data. RESULTS: Ultrasonographic readings were positively correlated with HRT measurements in both swollen (r = 0.62, P: = 0.002) and excavated disc (r = 0.84, P: < 0.0002). The 95% limits of agreement between the instruments were 0.24 +/- 0.59 mm (mean +/- 2 SD) and 0. 05 +/- 0.3 mm for swelling and cupping measurements, respectively. The coefficient of variation was 7.63% and 1.8% for swelling and 7. 93% and 5.91% for cupping, with US and HRT, respectively. CONCLUSIONS: The results indicate that US and CSLO readings are correlated i: both disc swelling and cupping conditions, but to a different extent because of a significant discrepancy in papilledema. US assessment can be considered highly reproducible. Combined US and HRT optic disc analysis may be recommended in papilledema evaluation as long as a better correlation can be demonstrated in further studies. (+info)Papilloedema with peripapillary retinal haemorrhages in an acquired immunodeficiency syndrome (AIDS) patient with cryptococcal meningitis. (6/183)
A case of cryptococcal meningitis in an AIDS patient who presented with optic disc edema, bilateral retinal and peripapillary haemorrhages is reported. (+info)Susac's syndrome: beneficial effects of corticosteroid therapy in a Japanese case. (7/183)
Susac's syndrome is a rare disorder characterized by the triad of microangiopathy of the brain and retina with hearing loss. More than 50 affected individuals have been reported worldwide, all Caucasians. We herein identify the first Japanese patient with Susac's syndrome. A 36-year-old man developed recurrent subacute encephalopathy, bi- a lateral sensorineural hearing loss, and retinal arteriolar occlusions, caused by microangiopathy from a year previously. T2-weighted MRI showed multiple high-signal lesions ti predominantly in the periventricular white matter. During the exacerbated phase both high-dose intravenous methyl-prednisolone and oral prednisone therapy produced beneficial effects. He showed definite remission within 2 years from the disease onset. (+info)Surgical treatment of chronic papilloedema in children. (8/183)
A surgical technique for optic nerve decompression in children is described and contrasted with other techniques described in the literature. The operation was effective in relieving long-standing disc oedema in two cases in which the swelling was due to raised intracranial pressure. Photographic evidence is presented. The indications for surgery and how its effect is exerted are discussed. (+info)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.
Pseudotumor cerebri, also known as idiopathic intracranial hypertension, is a condition characterized by increased pressure around the brain without any identifiable cause such as a tumor or other space-occupying lesion. The symptoms mimic those of a brain mass, hence the term "pseudotumor."
The primary manifestation of this condition is headaches, often accompanied by vision changes like blurry vision, double vision, or temporary loss of vision, and pulsatile tinnitus (a rhythmic whooshing sound in the ears). Other symptoms can include neck pain, nausea, vomiting, and papilledema (swelling of the optic nerve disc). If left untreated, pseudotumor cerebri can lead to permanent vision loss.
The exact cause of pseudotumor cerebri remains unknown, but it has been associated with certain factors such as obesity, rapid weight gain, female gender (particularly during reproductive years), sleep apnea, and the use of certain medications like tetracyclines, vitamin A derivatives, and steroid withdrawal. Diagnosis typically involves a series of tests including neurological examination, imaging studies (such as MRI or CT scan), and lumbar puncture to measure cerebrospinal fluid pressure. Treatment usually focuses on lowering intracranial pressure through medications, weight loss, and sometimes surgical interventions like optic nerve sheath fenestration or shunting procedures.
Intracranial hypertension is a medical condition characterized by an increased pressure within the skull (intracranial space) that contains the brain, cerebrospinal fluid (CSF), and blood. Normally, the pressure inside the skull is carefully regulated to maintain a balance between the formation and absorption of CSF. However, when the production of CSF exceeds its absorption or when there is an obstruction in the flow of CSF, the pressure inside the skull can rise, leading to intracranial hypertension.
The symptoms of intracranial hypertension may include severe headaches, nausea, vomiting, visual disturbances such as blurred vision or double vision, and papilledema (swelling of the optic nerve disc). In some cases, intracranial hypertension can lead to serious complications such as vision loss, brain herniation, and even death if left untreated.
Intracranial hypertension can be idiopathic, meaning that there is no identifiable cause, or secondary to other underlying medical conditions such as brain tumors, meningitis, hydrocephalus, or certain medications. The diagnosis of intracranial hypertension typically involves a combination of clinical evaluation, imaging studies (such as MRI or CT scans), and lumbar puncture to measure the pressure inside the skull and assess the CSF composition. Treatment options may include medications to reduce CSF production, surgery to relieve pressure on the brain, or shunting procedures to drain excess CSF from the intracranial space.
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.
Intracranial pressure (ICP) is the pressure inside the skull and is typically measured in millimeters of mercury (mmHg). It's the measurement of the pressure exerted by the cerebrospinal fluid (CSF), blood, and brain tissue within the confined space of the skull.
Normal ICP ranges from 5 to 15 mmHg in adults when lying down. Intracranial pressure may increase due to various reasons such as bleeding in the brain, swelling of the brain, increased production or decreased absorption of CSF, and brain tumors. Elevated ICP is a serious medical emergency that can lead to brain damage or even death if not promptly treated. Symptoms of high ICP may include severe headache, vomiting, altered consciousness, and visual changes.
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.
A headache is defined as pain or discomfort in the head, scalp, or neck. It can be a symptom of various underlying conditions such as stress, sinus congestion, migraine, or more serious issues like meningitis or concussion. Headaches can vary in intensity, ranging from mild to severe, and may be accompanied by other symptoms such as nausea, vomiting, or sensitivity to light and sound. There are over 150 different types of headaches, including tension headaches, cluster headaches, and sinus headaches, each with their own specific characteristics and causes.
The transverse sinuses are a pair of venous channels located within the skull. They are part of the intracranial venous system and are responsible for draining blood from the brain. The transverse sinuses run horizontally along the upper portion of the inner skull, starting at the occipital bone (at the back of the head) and extending to the temporal bones (on the sides of the head).
These sinuses receive blood from the superior sagittal sinus, straight sinus, and the occipital sinus. After passing through the transverse sinuses, the blood is then drained into the sigmoid sinuses, which in turn drain into the internal jugular veins. The transverse sinuses are an essential component of the cerebral venous system, ensuring proper blood flow and drainage from the brain.
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.
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.
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!
The Bruch membrane is a thin, layered structure that separates the retina from the choroid in the eye. It is composed of five layers: the basement membrane of the retinal pigment epithelium (RPE), the inner collagenous layer, the elastic layer, the outer collagenous layer, and the basement membrane of the choriocapillaris. The Bruch membrane provides structural support to the RPE and serves as a barrier between the retina and the choroid, allowing for the selective transport of nutrients and waste products. It also plays a role in maintaining the health of the photoreceptors in the retina. Damage to the Bruch membrane is associated with age-related macular degeneration (AMD), a leading cause of vision loss in older adults.
Flicker Fusion is the frequency at which an intermittent light stimulus appears to be completely steady or continuous to the average human observer. In other words, it is the rate at which a flickering light source transitions from being perceived as distinct flashes to a smooth and constant emission of light. The exact threshold can vary depending on factors such as the intensity of the light, its size, and the observer's visual acuity.
Flicker Fusion has important implications in various fields, including visual perception research, display technology, and neurology. In clinical settings, assessing a patient's flicker fusion threshold can help diagnose or monitor conditions affecting the nervous system, such as multiple sclerosis or migraines.
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.
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.
Cerebrospinal Fluid Pressure (CSFP) is the pressure exerted by the cerebrospinal fluid (CSF), a clear, colorless fluid that surrounds and protects the brain and spinal cord. CSF acts as a cushion for the brain, allowing it to float within the skull and protecting it from trauma.
The normal range of CSFP is typically between 6 and 18 cm of water (cm H2O) when measured in the lateral decubitus position (lying on one's side). Elevated CSFP can be a sign of various medical conditions, such as hydrocephalus, meningitis, or brain tumors. Conversely, low CSFP may indicate dehydration or other underlying health issues.
It is important to monitor and maintain normal CSFP levels, as abnormal pressure can lead to serious neurological complications, including damage to the optic nerve, cognitive impairment, and even death in severe cases. Regular monitoring of CSFP may be necessary for individuals with conditions that affect CSF production or absorption.
Tomography is a medical imaging technique used to produce cross-sectional images or slices of specific areas of the body. This technique uses various forms of radiation (X-rays, gamma rays) or sound waves (ultrasound) to create detailed images of the internal structures, such as organs, bones, and tissues. Common types of tomography include Computerized Tomography (CT), Positron Emission Tomography (PET), and Magnetic Resonance Imaging (MRI). The primary advantage of tomography is its ability to provide clear and detailed images of internal structures, allowing healthcare professionals to accurately diagnose and monitor a wide range of medical conditions.
The subarachnoid space is the area between the arachnoid mater and pia mater, which are two of the three membranes covering the brain and spinal cord (the third one being the dura mater). This space is filled with cerebrospinal fluid (CSF), which provides protection and cushioning to the central nervous system. The subarachnoid space also contains blood vessels that supply the brain and spinal cord with oxygen and nutrients. It's important to note that subarachnoid hemorrhage, a type of stroke, can occur when there is bleeding into this space.
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.
Echo-Planar Imaging (EPI) is a type of magnetic resonance imaging (MRI) technique that uses rapidly alternating magnetic field gradients and radiofrequency pulses to acquire multiple images in a very short period of time. This technique allows for the rapid acquisition of images, making it useful for functional MRI (fMRI) studies, diffusion-weighted imaging, and other applications where motion artifacts can be a problem.
In EPI, a single excitation pulse is followed by a series of gradient echoes that are acquired in a rapid succession, with each echo providing information about a different slice or plane of the object being imaged. The resulting images can then be combined to create a 3D representation of the object.
One of the key advantages of EPI is its speed, as it can acquire an entire brain volume in as little as 50 milliseconds. This makes it possible to capture rapid changes in the brain, such as those that occur during cognitive tasks or in response to neural activation. However, the technique can be susceptible to distortions and artifacts, particularly at higher field strengths, which can affect image quality and accuracy.
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.
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.