Optic neuritis or multiple sclerosis

SURVEY OF OPHTHALMOLOGY

CURRENT

VOLUME 31 - NUMBER 1 . JJLY~AUGUST

1986

OPHTHALMOLOGY

CREIG s. HOYT, EDITOR

Optic Neuritis or Multiple Sclerosis, by J .F. kTurtzke. Arch New01 42:704-7 10, 1985 This paper addresses the question of how often a first bout of isolated idiopathic optic neuritis progresses to multiple sclerosis. The author reviews all of the prospective and retrospective studies published to date in reference to this question. The author argues that recurrent optic neuritis is an entity separate from multiple sclerosis and occurs with no other evidence of dissemination in about 1 in 8 cases of optic neuritis. The author believes that the progression rates reported in excess of 40% are often in studies biased by major intrinsic flaws. He admits, however, that similar selection input bias may mar some of the studies with lower rates as well. The author’s opinion is that the diagnosis of optic neuritis is a clinical one and that only one-eighth to one-third of young adults with a first attack will go on to show clinical evidence of multiple sclerosis. (Reprint requests: ton,

DC

Dr. Kurtzke,

Neurology

Service

127, Veteran’s

hdministration

Medical

Center,

50 Irving

St.. NCV, PVashing--

20422.)

Comment The reported risk of patients with optic neuritis later developing multiple sclerosis varies greatly in different studies, as shown in Dr. Kurtzke’s article. Prognostic studies should be made together by ophthalmologists and neurologists if the conditions mimicking optic neuritis are to be excluded from the series. The diagnosis of so-called isolated optic neuritis is based on a negative neurological history and normal neurological examination. If the neurological history is not questioned carefully and a neurological examination not performed during optic neuritis, the number of patients with “isolated optic neuritis” will be too high. A careful history of patients often reveals some minor transient abnormalities despite the normal neurological examination so the patients do not fulfill the diagnostic criteria of multiple sclerosis. In my opinion, these patients should be followed up, but the patients with isolated optic neuritis should be analyzed as a separate group. Today it might be interesting to have nuclear magnetic resonance imaging of the brain from the patients with isolated optic neuritis because this study might reveal plaques in their white matter. The prognostic studies of optic neuritis should be based on a careful neurological examination of the patients at least five years from the episode ofoptic neuritis. In some population-based studies the prognosis is based only on medical records or multiple sclerosis registers. Those studies are not comparable with prospective tiJlow-up examinations. The two Finnish articles cited in Dr. Kurtzke’s article, represent an example. In one study was a population-based survey. The prognosis was based on the number of patients with optic neuritic later developing multiple sclerosis according to the medical records and multiple sclerosis register (Kinnunen E: Acta Neural &and 68:371-377, 1983). In this study the prognostic figure was only 19%. In the other study, the prognostic figure was based on a personal neuro-ophthalmological and neurological reexamination ofthe patients 5-10 years after the first episode ofoptic neuritis (Nikoskelainen E, Frey H, Salmi A: Ann ‘Veurol 9:545-550, 1981) and 71% of patients with isolated optic neuritis and 75% in the total patient material had developed multiple sclerosis. I believe that optic neuritis in most young or middle-aged persons (excluding vascular, toxic or hereditary causes) is a sign of multiple sclerosis. The disease often has a benign course. EI.:\~..\ NIKoSKI~l.~\lS~:N, b1.11. 7rt~Ktil.,

Unless otherwise indicated, additions by Dr Hoyt.

the abstracts

appearing

here are taken from the origlnal publications

73

with appropriate

FINI..~\NI)

modifications

and