Subacute sclerosing panencephalitis. Imaging and clinical correlation.

Twenty-one patients at different clinical stages of subacute sclerosing panencephalitis were studied by magnetic resonance imaging and computed tomography. In patients in the early clinical stage, the imaging studies appeared normal. Within 6 months, diffuse or focal areas of high signal on T2-weighted magnetic resonance images were evident. Progressive hemispheric, cerebellar, and brainstem atrophy was seen later. Lesions of the deep nuclei were noted frequently in patients in the early and intermediate stages, with the lentiform involved more than the caudate. Magnetic resonance imaging was better than computed tomography in illustrating white matter and basal ganglia abnormalities. Radiographic progression occurred regardless of clinical course.