[The value of visually evoked response in diagnosis of multiple sclerosis ].

We investigated the reliability of visually evoked responses (VER) in 56 cases in diagnosing multiple sclerosis. We found 100% pathological VER in proved cases and 71% in probable/possible cases. Patients with a duration of illness less than one year had in 80% pathological VER, whereas in other conditions only 17% were pathological. Structural changes are usually found in definite multiple sclerosis patients with a disease progress lasting more than 1 year. Pathological VER are an important diagnostic aid in multiple sclerosis, especially in doubtful cases, whereas structural investigations are primarily useful in the exclusion of other conditions.