Cranial magnetic resonance imaging in patients with tuberous sclerosis and normal intellect.

The pattern of cerebral hamartomas among a population of patients with tuberous sclerosis and normal intellect was determined. All patients with tuberous sclerosis over 5 years old with normal intellect who were resident in the Bath health district were offered cranial scanning by magnetic resonance imaging. Cerebral axial and coronal images were obtained in 10 mm contiguous sections with a Picker 0.5 tesla magnetic resonance imaging unit. The number, size, and distribution of lesions found was recorded. Eleven of 13 eligible patients underwent scanning. Two patients had normal scans. Seven patients had between one and five subependymal nodules. Nine patients had between two and nine cerebral tubers best seen on T2 weighted images. Our findings suggest that the wrong conclusions may be drawn if the number of lesions alone is used to predict neurological outcome in tuberous sclerosis.