Acute optic neuritis and the prognosis for multiple sclerosis.

In a retrospective survey of acute optic neuritis 144 cases in adults were found and, of these, 127 were reviewed, five had died of causes related to multiple sclerosis, and 12 were lost to follow-up. There was a statistically significant seasonal variation in the incidence of optic neuritis. When the life-table method of analysis was used, the probability of developing multiple sclerosis rises to 78% 15 years after an episode of optic neuritis. At review, 49 (73%) of the 67 patients with multiple sclerosis were independent and leading active lives.