T1 coronal post gad T1 axial post gad FIR axial

Diagnosis: Tuberous sclerosis

Tuberous sclerosis is an autosomal dominant phacomatosis which has been identified on chromosomes 9 and 11. The classic triad of seizures, mental retardation, and adenoma sebaceum is present in only 1/2 of patients. CNS abnormalities in tuberous sclerosis include subependymal nodules, cortical tubers, subependymal giant cell astrocytomas, and a non-specific white matter abnormality.

The subependymal nodules which are also known as subependymal hamartomas are seen in up to 95% of the patients with tuberous sclerosis. Most occur near the caudate head and typically calcify. 80% of subependymal nodules will enhance which is not indicative of malignant degeneration. Subependymal giant cell astrocytomas are always adjacent to the foramina of Monro. Calcification as well as intense enhancement are typical. SGCAs are histologically benign however they often grow and cause obstructive hydrocephalus. Most tuberous sclerosis patients demonstrate cortical tubers which are best identified on T2 as subcortical foci of increased signal. They have decreased signal on T1 and generally do not enhance.

The non-specific white matter abnormality of tuberous sclerosis is believed to consist of dysplastic white matter which may be seen as bands of increased T2 signal which extend from the ventricles to the cortical surface. The phenotype of tuberous sclerosis also includes renal angiomyolipomas, cardiac rhabdomyomas, hypopigmented skin lesions (ash leaf spots), shagreen skin patches, and retinal hamartomas. There is no differential in a case which includes findings here of enhancing foramina of Monro masses compatible with subependymal giant cell astrocytomas, subependymal nodules and multiple foci of cortical and subcortical white matter signal abnormalities compatible with cortical tubers. Related Cases

Cortical dysplasia Tuberous sclerosis Tuberous sclerosis