Tumors in the temporal horn of the lateral ventricle as a cause of epilepsy.

Three neoplastic lesions located in the temporal horn of the lateral ventricle were diagnosed after the onset of seizures. Neither hydrocephalus nor temporal horn entrapment were present. The complete surgical removal of the tumor resulted in the disappearance of the epileptic episodes in 2 cases; the third patient refused surgery, and his lesion appears unmodified after a 3-year follow-up. Histological examination led to a diagnosis of choroid plexus papilloma in 1 case and of neurocytoma in the other; in the third case, the nonextracted lesion was presumed to be a partially calcified choroid plexus papilloma. The mechanism underlying the seizures in the 2 operated children is speculated to be a compression exerted upon the mesial temporal structures that form the medial wall of the temporal horn of the lateral ventricles; this compressive activity was resolved by removal of the tumor, and the epileptic episodes consequently disappeared in the 2 operated children; seizures were controlled by drugs in the third child.