Abstracts

Rationale: Hypermotor (hyperkinetic) seizures are characterized by prominent limb and trunk movements and have been described to typically originate from the frontal lobes and to occur during the night. Methods: We analyzed the records of 890 patients admitted to our epilepsy monitoring unit. All seizure evolutions had been classified prospectively independent of the other clinical results based on a semiological seizure classification system. If the patient had seizures classified as hypermotor seizures, we reanalyzed all video and EEG recordings of that individual patient. We classified part of a seizure evolution as hypermotor if the patient had at least 3 repetitions of large movements of the trunk or extremity movements with a maximum in the proximal joints. We further analyzed the time distribution of the hypermotor seizures over the day and we scored the sleep/wake state of the patient directly before the seizure and 30 seconds before the seizure onset. Results: We identified 52 patients with a total of 426 hypermotor seizures. Hypermotor seizures were more common in frontal lobe epilepsies (FLE; 32 of 152 FLE patients; 21.1%) than in temporal lobe epilepsies (TLE: 10 of 339 patients, 5.1%; p<0.0001) or parieto-occipital lobe epilepsies (POLE: 2 of 39, 6.1%; p<0.0001) hypermotor seizures were uncommon. In 8 patients with hypermotor seizures, the epilepsy could not be localized to only one lobe. Hypermotor seizures were twice as common during the night (22:00 - 6:00; FLE 49.7%; non-FLE 44.8%) than during morning/noon (6:00 - 14:00; FLE 27.3%; non-FLE 27.6%) or during the afternoon/evening (14:00 - 22:00; FLE 23.1%; non-FLE 27.6%). The sleep stages before the seizure differed between FLE and TLE patients. In FLE 46.3% of the seizures developed out of sleep, compared to only 23.1% of the seizures in TLE (p<0.01). This relation was identical 30 seconds prior to seizure onset (FLE: 53.7% vs TLE: 28.2%; p<0.01).