FAMILIAL BILATERAL PERIVENTRICULAR NODULAR HETEROTOPIA MIMICS TUBEROUS SCLEROSIS

A mother and daughter with an initial diagnosis of tuberous sclerosis are described. The daughter presented with partial seizures at the age of 8 months. Computed tomography showed uncalcified periventricular n odules which on magnetic resonance imaging were ovoid, almost contiguo us, of grey matter density, and did not enhance with gadolinium. Brain imaging of her asymptomatic mother was similar. Absence of severe men tal retardation, extracranial hamartomas, and depigmented patches dist inguishes familial bilateral periventricular nodular heterotopia (FNH) from tuberous sclerosis. FNH is probably inherited as an X linked dom inant with lethality in males.