Term
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Definition
| Disease where the myelin sheath is abnormally formed (mostly related to inherited metabolic disorders) |
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Term
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Definition
| Disease where the myelin sheath is normally formed but is then the primary target for destruction. The primary example is multiple sclerosis. In the classic lesions, myelin is lost but the central axon remains relatively intact. |
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Term
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Definition
each wrap around
numerous axons |
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Term
| dysmyelinating diseases there are basically two types |
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Definition
--Those primarily affecting white matter (e.g. adrenoleukodystrophy, metachromatic leukodystrophy
--Those primarily with accumulation of myelin byproducts in neurons (e.g. Tay Sachs disease, Nieman Pick disease) |
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Term
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Definition
--Inflammatory, autoimmune disease of the Central Nervous System
--Characterized by relapsing neurologic symptoms, and progressive impairment in function
--Immensely variable symptoms and signs including: Monocular vision loss, Brainstem (cranial nerve deficits), Motor/Sensory impairments, imbalance |
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Term
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Definition
--Motor weakness, paresthesias, impaired vision, double vision, intention tremor, ataxia.
--The ability of MRI to show clinically silent lesions has greatly added in establishing the diagnosis in the disease’s early phases. |
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Term
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Definition
-Intention tremor, nystagmus, scanning speech.”
-Points to the white matter pathways to and from the cerebellum
-Vulnerable areas for a demyelinating, white matter disease |
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Term
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Definition
-most common form of involvement of the visual pathways by MS. It is also a common presenting feature (~20-25% of cases
-Over a period of several days there is partial or complete loss of vision in one eye
--acute unilateral eye pain, classically accentuated by eye movement |
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Term
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Definition
a scotoma* (mainly of central vision) can be demonstrated. Bilateral optic neuritis is rare in MS
--about half of patients swelling (edema) of the optic nerve head (papillitis) is seen on fundoscopic exam. |
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Term
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Definition
| Scotoma- an isolated area of the visual field with absent vision |
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Term
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Definition
--About 1/3 of patients with optic neuritis recover completely and most of the remaining patients improve substantially
--Half of all patients who present with optic neuritis alone will eventually develop other signs of MS…more on this later |
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