ANALYSIS OF SEIZURE MANIFESTATIONS OF PURE FRONTAL-LOBE ORIGIN

With the intention of subclassifying frontal lobe epilepsies based on ictal semiology, we scrutinized the seizure manifestations in 18 patie nts with ''pure'' frontal lobe epilepsy who underwent corticectomy res tricted to the frontal lobe after undergoing invasive long-term EEG/vi deo monitoring and achieved excellent seizure outcome. All patients ha d well-localized lesions. By combining principal seizure manifestation s unequivocally appearing during the ictal events, we were able to sub divide the patients into the following three groups: group 1, suppleme ntary motor seizures with tonic posturing and other relevant symptoms with consciousness retained; group 2, focal motor seizures with elemen tary clonic and/or tonic symptoms with consciousness also retained; an d group 3, psychomotor seizures with various automatisms usually accom panying impairment of consciousness. In addition, localization of the epileptogenic lesions enabled us to conclude that in both the focal mo tor seizure group and the supplementary motor seizure group the epilep togenic zones were restricted to the posterior third of the frontal lo be generating somatomotor manifestations, whereas in the psychomotor s eizure group the epileptogenic zones were largely in the anterior two thirds of the frontal lobe, where there may be no neuronal substratum primarily generating seizure manifestations. The electroclinical progr ess of psychomotor automatisms in 3 patients is presented in relation to seizure spread.