Abstracts

Rationale: The analysis of semiological elements can contribute to the classification of epileptic seizures, and to the generation of hypotheses about the localization of the epileptogenic zone in patients with focal epilepsy. We analyzed semiological characteristics of gelastic epilepsy in a homogeneous group of 23 patients with hypothalamic hamartomas. Methods: 230 video-eeg-documented seizures from 23 patients were included in the analysis. All suffered from drug-resistant focal gelastic epilepsy due to hypothalamic hamartomas and underwent presurgical monitoring. Mean age of patients was 24.2 ± 11.9 years, 8 patients were female. Auras and motor-elements of seizures were documented and analyzed descriptively on a patient basis.Results: The most common aura type was epigastric (occurring in 17.4% of patients), less common were cephalic and visual auras (present in 8.7% of patients). Motor phenomena included tonic, clonic, dystonic and hypermotor movements as well as automatisms. 52.2 % of patients had bilateral tonic, 47.8 % unilateral tonic phenomena. Clonic phenomena were noted bilaterally in 26.1% and unilateral in 30.1 % of patients. Dystonia and eyelid myoclonia were less common (17.4% each). Hypermotor movements occurred in 21.3% of patients, manual automatisms in 43.5% and oral automatisms in 30.4% of patients.Conclusions: Semiologic characteristics included typical elements of temporal and frontal lobe seizures. Particularly frequent were bilateral tonic and clonic elements. Gelastic seizures are thus difficult to differentiate from seizures of temporal or frontal origin not only regarding EEG findings but also when taking into account characteristic semiological elements except for periods of laughter.