Roles of a subependymal nodule of tuberous sclerosis on pathophysiology of epilepsy.

Polysomnographies (PSG) were performed on two cases with tuberous sclerosis (TS), both having subependymal nodules on the medial wall of the caudate nucleus adjacent to the thalamostriatal sulci. Clinically one had suffered from infantile spasm and which later turned out to be complex partial seizure with a rotation toward the right. The other had developed tonic seizure on the right with a rotation toward the left in early childhood. Clinico-pharmacological studies revealed the existence of synaptic supersensitivity of the dopamine (DA) receptor in the left caudate and PSG confirmed the synaptic supersensitivity of the former, while in the latter case, it suggested a decrease in DA activity on the left. Subependymal nodules in the caudate nucleus could cause a reduction in the DA transmission and develops synaptic supersensitivity after suffering from TS.