SUBSIDENCE OF SEIZURE-INDUCED BY STEREOTACTIC RADIATION IN A PATIENT WITH HYPOTHALAMIC HAMARTOMA - CASE-REPORT

The authors report on a patient who exhibited intractable epilepsy due to an inaccessible hypothalamic hamartoma and subsequently underwent stereotactic radiosurgery. This 25-year-old man had a 24-year history of intractable gelastic and tonic-clonic seizures. Magnetic resonance (MR) imaging performed at examination as well as that performed 30 mon ths earlier demonstrated a nonenhancing and nonprogressive spherical m ass, approximately 10 mm in diameter, located on the patient's right s ide at the floor of the third ventricle. Focal radiation treatment per formed with a gamma knife unit administered 36 Gy to the center and 18 Gy to the periphery of the lesion. This treatment resulted in an impr ovement in seizure control. Before the patient underwent radiosurgery, he suffered from three to six greneralized seizures per month in spit e of attentive compliance with an anticonvulsant medication regimen. A fter irradiation of the harmatoma, the frequency of the seizures trans iently increased and then subsided 3 months posttreatment. The patient has been free of seizures for the last 21 months, with no neurologica l or endocrinological complications. Magnetic resonance imaging perfor med 12 months posttreatment demonstrated complete disappearance of the lesion.