In a population of 21 patients with longstanding static multiple sclerosis (MS), 71% were found to have electroencephalographic abnormalities on serial testing. This did not seem to correlate with the clinical localization of their disease or its duration.
Electroencephalographic abnormalities seem to reflect the simple presence of lesions in the cerebrum of chronic MS patients whether or not these lesions produce clinically detectable signs.
Electroencephalograms may be valuable in the diagnostic evaluation of possible MS, even in patients in clinical remission, in that this test may provide the only sign of cerebral involvement.
Goldstein MN, Satran R. Serial Electroencephalographic Observations in Chronic Multiple Sclerosis. Arch Intern Med. 1974;134(6):1055-1058. doi:10.1001/archinte.1974.00320240089010