Outcome of Callosotomy in Treatment of Intractable Epilepsy

Kim, Dong Seok; Choi, Joong Uhn; Chung, Sang Sup; Lee, Beyng In

Abstract

The purpose of the present study was to verify the effect of callosotomy on generalized seizures, to check the effect on other seizure types and to search for possible prognostic factors. Twenty-one patients with a minimum follow-up of one year were available for our analysis. Mean follow up duration was 3.1years(1 to 7years). In four of them the total callosotomy was performed in two stages(total: 25 surgical procedures). Age ranged from 7 to 37years(mean 19.4years). Different aetiologies were known in 10 patients. Duration of epilepsy ranged from 2 to 23years(mean 8years). The frequency of seizures ranged between 5 and 300 per month. The most significant effect of surgery was the complete suppression of the generalized seizures associated with falling in 12/21 and their reduction of more than 75% in 6/21 patients. Sixteen(84.2%) of 19 patients with generalized tonic-clonic seizure had a significant reduction in automatisms: this reduction consisted of simplification of automatic movements and shorter duration of seizures. The surgical effect on the partial seizures was variable. The role of age, aetiology, duration of the disease, single or more seizure types and mental impairment remains uncertain. Mild disconnection syndrome appeard in 4 patients although the splenium was spared. Second opeartion, total callosotomy, could signigicantly suppress the generalized seizures associated with falling without disconnection syndrome. The present findings confirm that the main indication for callosotomy is generalized seizures with fall. Surgery can be initially limited to the anterior 2/3 of the corpus callosum; further posterior section of the corpus, excluding the splenium, should be regarded as a second step, when necessary.