Computed tomography: regression of periventricular enhancing lesions in multiple sclerosis.

A patient with two periventricular enhancing lesions on computed tomography subsequently demonstrated clearing of these abnormalities without treatment and a clinical course compatible with multiple sclerosis. CT scans obtained in disease processes associated with acute demyelination and alteration of the blood-brain barrier can show enhancing lesions. These lesions can initially be confused with primary or secondary neoplasms, enhancing infarcts or arteriovenous malformation. The differential diagnosis of enhancing lesions without significant mass effect should initially include the acute phase of multiple sclerosis and other demyelinating processes.