General Medical Information

Multiple Sclerosis

Frank E. Lucente
Samir Shah
Roger Kula

Multiple sclerosis is an inflammatory disease involving areas of demyelinization in the central nervous system. This disease primarily affects young adults and is characterized by exacerbations and remissions. The geographic distribution is distinct: the incidence is higher in the higher latitudes and almost nil at the equator. Vertigo is the presenting problem among 7% to 10% of patients and may eventually occur among as many as 30% of patients. Nystagmus occurs among 70% of patients. This is usually horizontal nystagmus, although 33% of patients with nystagmus have vertical nystagmus. Diplopia often is caused by involvement of extraocular muscles from lesions in the medial longitudinal fasciculus, which links the nuclei of cranial nerves VI and III and subserves conjugate lateral gaze. Bilateral internuclear ophthalmoplegia due to a lesion of the medial longitudinal fasciculus strongly indicates the existence of multiple sclerosis. Deafness is rare in multiple sclerosis. The Charcot triad in multiple sclerosis consists of nystagmus, scanning speech, and intention tremor (5). Multiple sclerosis can be diagnosed reliably with appropriate diagnostic studies. The following findings establish the diagnosis: magnetic resonance images that show small, demyelinated foci in the white matter; abnormal brainstem auditory or visual evoked responses, and elevated protein level in the cerebrospinal fluid with the presence of oligoclonal immunoglobulin banding.