Seizure outcome after corpus callosotomy: the Taiwan experience

From September 1989 to August 1996, we performed anterior corpus callosotomy in 83 patients. Unfortunately, 9 patients were lost to follow-up. Among the remaining 74 patients, 59 had Lennox-Gastaut syndrome (evolved from infantile spasms in 22), 9 had complex partial seizures with or without secondary generalized seizures, 1 had multifocal independent epileptogenic foci (MISF) syndrome, 3 had hemiconvulsion-hemiplegia-epilepsy (HHE), and 2 had infantile spasms. All cases were followed up for at least 2 years after surgery. The highest rate of significant improvement (more than 50% reduction in seizure frequency) was noted in the patients with generalized tonic-clonic seizures, 82.1% of whom experienced significant improvement, followed by those with generalized tonic seizures (76.7%), atonic seizures (72.7%), myoclonic seizures (64.9%), atypical absences (58.6%), and complex partial seizure with or without secondary generalization (61.5%). Complete freedom from seizures was noted in 14 cases (18.9%). One patient had the anterior half of his right palm amputated following radial artery thrombosis complicated by insertion of an arterial line during anesthesia. Otherwise, there were no major postoperative complications except for brief mutism and multifocal jerks in some patients during the Ist postoperative week. Thus, we conclude that corpus callosotomy is a safe alternative treatment for all kinds of medically intractable seizures, especially generalized epilepsy.