Atypical early manifestations of multiple sclerosis (MS) are common in children and young adults. 6 patients (aged 5 to 33 years) were examined by MR because of confusing neurological manifestations. In addition to small MS lesions there were also large intracerebral lesions which, however, did not occupy additional space but which looked more like tumours or abscesses. The lesions were sharply demarcated cystic formations with margins that enhanced with contrast. The diagnosis of these lesions presents difficulties, the differential diagnosis including MS and its variants, neoplastic, infectious and vascular processes. MR can provide valuable diagnostic information.