Pediatric-onset gelastic seizures: clinical data and outcome.

Gelastic seizures are an extremely rare form of epilepsy defined as automatic bouts of laughter without mirth commonly associated with a hypothalamic hamartoma. The objective was to survey all Israeli children found to develop recurrent gelastic seizures and report presenting symptoms, electroencephalographic and radiologic data, and response to either antiepileptic drugs or surgery. Ten children who developed gelastic seizures at the age of 1 week to 6.5 years (mean, 25 months) at a frequency from 3 bouts per week to >10 prolonged bouts per day were followed for a period of 1.3-12 years (mean, 6 years). Seven cases were defined as symptomatic: cortical magnetic resonance imaging revealed a hypothalamic hamartoma in four patients and cortical abnormalities in three others. Seizure control was achieved in four patients, including a neonate with status gelasticus and hypothalamic hamartoma, and partial control in one more. Five children remained resistant to polytherapy, including three with hypothalamic hamartoma even after two of them underwent hemartoma excision. Thus, children with gelastic seizures may respond relatively well to drug therapy. Four of the 10 patients became seizure free with drug therapy; in three intractable symptomatic cases, surgery was tried but failed in two of the three.