Variations of brain stem auditory evoked potentials correlated to duration and severity of multiple sclerosis.

A total of 158 recordings of brain stem auditory evoked potentials (BAEPs) were obtained in 121 patients with multiple sclerosis. A statistically significant increased incidence of abnormality and diffusely abnormal recordings was found with increasing duration and severity of symptoms. Alterations in follow-up recordings might reflect changes in the clinical state, but also occurred in clinically stable patients. These findings suggested that transition from normality of BAEPs might occur either by successive disappearance of the later waves or by uniformly decreasing amplitudes of all the waves to diffusely abnormal recordings. It was concluded that the main value of BAEP recording in patients with multiple sclerosis was to indicate clinically silent lesions, and its value in monitoring the clinical condition of the individual patient was dubious.