Magnetic resonance imaging, evoked responses and cerebrospinal fluid findings in a follow-up study of children with optic neuritis.

Fourteen patients with previous optic neuritis (ON) in childhood were examined by magnetic resonance (MR) imaging from two months to 14 years after the onset of symptoms. Five patients had a single monosymptomatic course of ON but 7 developed multiple sclerosis (MS); 2 had another demyelinating disease. Eight patients had high signal intensity areas in the T2 weighted images compatible with MS plaques in MR scan; 2 with monosymptomatic ON, 5 with MS and one with another demyelinating disease. The plaques were periventricular or in the optic radiation. The plaques could already be seen during the first symptoms of ON. All 7 MS patients had abnormal visual evoked response, 3/4 abnormal somatosensory evoked response and 5/6 intrathecal immunoglobulin production, when examined at onset of optic neuritis or at follow-up. All patients except one, with lesions in MR, had either oligoclonal CSF antibodies or Dr2 HLA antigen. We suggest that MR is a very sensitive test showing MR abnormalities in children with ON. It is an important tool in the early assessment of MS.