Abstract
The brains of 110 patients with multiple sclerosis (MS) were examined by computer tomography (CT) with the fine matrix EMI scanner. In 41 cases (37 per cent) areas of low X-ray attenuation were demonstrated with elective location in the white matter around the anterior and posterior horns of the lateral ventricles. These areas are postulated to represent the well-known large periventricular plaques in MS. Contrast enhancement provided no further informattion. Cerebral plaques were concomitant to ventricular enlargement and/or cortical atrophy. Cerebral atrophy without demonstration of plaques was found in 50 cases (45 per cent) and only 19 patients (17 per cent) had normal CT scans. No difference was demonstrated between duration of disease or age at onset in plaque cases, atrophy cases and patients with normal EMI scans. The postulate regarding the nature of the low absorption areas in CT still awaits the verdict of future brain autopsies.