Cryptogenic gelastic epilepsy of frontal lobe origin: a paediatric case report.

Gelastic (laughing) seizures are an uncommon seizure type which in most cases has an organic cerebral pathology and specifically a hypothalamic hamartoma. The interictal EEG frequently shows focal activity. This report describes a 3 1/2-year-old boy who presented with episodes of unmotivated laughter associated with other epileptic symptomatology before the age of 3 years. Prolonged ambulatory EEG monitoring recorded electroclinical seizures starting in the right frontal area and spreading to the adjacent frontotemporal region. Neurological examination and brain magnetic resonance imaging were normal. Vigabatrin resulted in immediate remission of the seizures and normalization of the EEG.