The significance of brain magnetic resonance imaging abnormalities at presentation with clinically isolated syndromes suggestive of multiple sclerosis. A 5-year follow-up study.

A 5-year follow-up study was performed on 89 patients who had undergone brain magnetic resonance imaging (MRI) at presentation with an acute clinically isolated syndrome of the optic nerves, brainstem or spinal cord of a type suggestive of multiple sclerosis. At presentation, MRI was abnormal, revealing one or more asymptomatic cerebral white matter lesions in 57 (64%), and was normal in 32 (36%). At follow-up, progression to clinically definite multiple sclerosis had occurred in 37 out of 57 (65%) with an abnormal MRI and one out of 32 (3%) with normal MRI. Human leucocyte antigen (HLA) typing was performed in 70 patients and cerebrospinal fluid (CSF) was examined at presentation in 36. The presence of HLA-DR2 antigen or cerebrospinal fluid oligoclonal IgG bands were both associated with a significantly increased risk of progression to multiple sclerosis, but MRI was much more powerful in predicting outcome. The presence of four or more MRI lesions at presentation was associated with a higher rate of progression to multiple sclerosis, more frequent development of moderate or severe disabilities and a greater number of new MRI lesions at follow-up. The results indicate that brain MRI at presentation with a clinically isolated syndrome suggestive of multiple sclerosis is a powerful predictor of the clinical course over the next 5 years. This observation, combined with an ability to detect other sometimes treatable disorders which can also cause such syndromes, suggests that MRI is the investigation of choice in evaluating this group of patients.