Anterior callosotomy in epileptics with multiform seizures and bilateral synchronous spike and wave EEG pattern

Cerebral commissurotomy is a well established procedure in the treatment of epileptics refractory to drug therapy. Breeching of the ventricles in complete commissurotomy carries a certain morbidity. This has led others to perform operations in which the entire corpus callosum or only its anterior portion with or without the anterior commissure were sectioned. Sectioning of the anterior corpus callosum alone is justified by: a) frequent appearance in patients of seizures attributable to a frontal focus, b) clinical and experimental evidence that frontal discharges spread across the corpus callosum leading to subsequent generalized its, c) the attempt to understand the mechanisms involved in generalized seizures, d) even further reduced surgical morbidity and neuropsychological disability. Five epileptics were submitted to anterior callosotomy. The seizures in all of them suggested a frontal focus and consisted of absences, adversive, tonic, atonic, and tonic-clonic attacks. All patients were incapacitated by the frequency of seizures. Their EEGs showed paroxysms of bilateral synchronous slow spike and wave with uni-, or multiple (including bilateral symmetrical) focal accentuation. In two patients there were additional independent temporal lobe discharges. Neuropsychological evaluation showed cognitive deficits caused by inattention paroxysms and absences. After anterior callosotomy there was marked reduction in frequency of all types of seizures, the greatest improvement being in the reduction of frequency of absences. There was a marked decrease in physical, social and neuropsychological disabilities.