ABSTRACT
I. MULTIPLE SCLEROSIS A. Clinical Course The clinical course of multiple sclerosis (MS) is unpredictable and varies from death within weeks of onset to a completely asymptomatic course after initial symptoms. The diagnosis of MS rests on the ability to demonstrate white matter lesions in the central nervous system (CNS) disseminated both in time and space. Magnetic resonance imaging (MRI) is the imaging procedure of choice for the diagnosis of MS. MRI can also evaluate the progression of pathology and has become important in monitoring clinical trials. As of yet there is no cure for MS, although recently it has been shown with the aid of MRI that interferon /3-lb (IFN /3-ib) therapy reduces disease activity and may delay the progression of the disease (1).
B. Etiology and Pathogenesis The cause and pathogenesis of MS are unknown, but there appears to be an autoimmune response targeted against myelin and/or oligodendrocytes. The pathological hallmark is the demyelinated plaque. Within the early plaque, axons are usually preserved. Prineas, in looking at the early lesion (2), has found that macrophages strip myelin off the axons. The active macrophages contain myelin debris, including neutral fat, in their cyto-
