[A case of hypothalamic hamartoma with refractory seizures: successful treatment with gamma knife surgery].

Hypothalamic hamartomas are associated with precocious puberty and gelastic epilepsy. The seizures are often refractory to antiepileptic medications. The treatment of hamartoma is not well established. We report a 3-year-6-month-old boy was admitted because of intractable seizures occurring several times a day. The findings on magnetic resonance imaging and his characteristic seizure led to the diagnosis of hypothalamic hamartoma. The seizures were resistant to multiple antiepileptic drugs, and persisted for about 3 years, during which his cognition deteriorated. Focal radiosurgery by a gamma knife of the hamartoma successfully controlled the seizures with no neurological complications, and his mental function improved.