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PapilledemaSwelling of the optic nerve caused by increased intracranial pressure. EpidemiologyIncreased intracranial pressure (ICP) may result from brain tumor at any age and in either gender. Intracranial masses that obstruct cerebral spinal fluid (CSF) outflow may be relatively small and still result in dramaticly increased ICP and papilledema. Pseudotumor cerebri (also known as idiopathic or benign intracranial hypertension) characteristically presents in obese women of childbearing age. In this condition there is increased pressure similarly as if caused by a brain tumor, but no tumor is present. Infection can result in meningitis at any age and in any gender. Inflammation due to sarcoidosis is more common in African Americans and Scandinavians. Predisposing factors of papilledema include a history of carcinoma or lymphoma, and recent viral, bacterial, or tuberculous (TB) infection. Risk factors for increased ICP include recent weight gain, use of exogenous (extra not created by the body) estrogen or vitamin A, and intake of certain drugs (antibiotics, corticosteroids, isotretinoin (types of acne medication). Symptoms and signsSymptoms of increased ICP include headache, transient visual obscurations, intracranial noises (humming or ringing), decreased vision, and double vision. Headache is a common symptom; it is typically present upon awakening and associated with nausea and vomiting, but may be nonspecific in character. A decrease in peripheral vision, especially in the nasal quadrant, can eventually progress to central visual loss in some cases. Early papilledema is associated with bilateral (both eyes), although frequently asymmetric, loss of bilateral nerve fiber layer, lack of spontaneous venous pulsation (a visible pulsating of the main vein in the optic nerve able to be seen by your eye doctor), and loss of central cup. Hemorrhages and exudates (leakage from blood vessels) may also occur. In chronic papilledema, small additional blood vessels and white masses on the disc surface may be present, and afferent function may be abnormal (central visual acuity, color, pupils, and visual fields) with chronic papilledema, choroidal folds (Paton lines) or optic atrophy may result. Rarely, subretinal neovascularization (growth of new blood vessels) develops in the retina and causes subsequent leakage of blood and fluid. DiagnosisBilateral disc edema is a clinical diagnosis that is not appropriately termed papilledema until increased intracranial pressure is diagnosed. The differential diagnosis of bilateral disc swelling includes malignant hypertension, central retinal vein occlusions, anterior ischemic optic neuropathy, papillitis or optic nerve involvement by inflammation, infection, or neoplasia (abnormal cell proliferation); none of these entities disrupt spontaneous venous pulsations. Occasionally, a patient will present with headaches and atypical appearing optic nerves. “Pseudo-papilledema” may be diagnosed due to optic nerve head drusen, anomalous optic nerves, hyperopic nerves, or tilted discs. ManagementAlthough vision function may be normal in the early stages of papilledema, formal visual field testing is key to management at all stages. Neuroimaging, preferably MRI, is performed to look for an intracranial mass. In patients with persistent papilledema or who are unusual or unresponsive to medication, magnetic resonance venography should be considered as a diagnostic tool to exclude venous thrombosis. When the lumbar puncture is performed, opening pressure should be documented and the CSF should be analyzed for cells, glucose, and protein content. Management is dependent on the underlying cause of the increased intracranial pressure. If a tumor is present, surgical intervention is necessary. If pseudotumor cerebri is diagnosed, weight loss should be encouraged and the patient followed very closely with visual field testing. Failure to monitor visual fields can result in permanent visual loss and even blindness. If visual field defects are present the patient should be placed on a minimum of 1 g acetazolamide (Diamox) to lower pressure. If medical therapy fails to relieve the headache or visual loss progresses, surgical options should be discussed. A shunt may be placed by a neurosurgeon to drain CSF. Optic nerve sheath fenestration (surgery directly relieving pressure on the optic nerve) is indicated if a shunt fails to normalize the visual field or there is catastrophic visual loss with mild or absent headache.
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The most common presenting ocular symptom of papilledema is transient visual obscurations that are described as graying or blacking out of vision that lasts only for seconds and can be precipitated by moving from a lying to a sitting or standing position. Many patients notice a whooshing sound in one or both ears when lying down. Less frequently, horizontal diplopia (double vision) that is most prominent at a distance is the first symptom of a sixth nerve palsy associated with the increased intracranial pressure. Retroorbital (behind the eye) ache is sometimes present and may be worse with eye movement.
