Do tubers contain function? Resection of epileptogenic foci in perirolandic cortex in children with tuberous sclerosis complex

Abstract

PURPOSE: Surgical resection of single, dominant, epileptogenic lesions in patients with tuberous sclerosis complex (TSC) is now accepted as an effective therapy. However, patients with symptomatic tubers in eloquent cortex are sometimes not offered surgery because of the concern for postoperative neurologic morbidity. In this study, we examine our results in children undergoing surgery for resection of tubers and associated seizure foci in rolandic and perirolandic cortex. METHODS: Between 1998 and 2008, 52 pediatric patients (mean age 4 years) with TSC underwent epilepsy surgery at the NYU Comprehensive Epilepsy Center. Fifteen of these patients underwent multistage surgery for invasive mapping of seizure foci and surrounding functional cortex followed by resection of tubers/seizure foci in or near rolandic cortex. Data were retrospectively collected and neurologic outcomes were tabulated. RESULTS: Postoperatively, four patients (27%) had either new hemiparesis or worsening of a preexisting hemiparesis. However, all patients were back to their neurologic baselines at 3-month follow-up, yielding no permanent postoperative deficits. The modified Engel outcome was class I in nine patients (60%), class II in three patients (20%), class III in two patients (13%), and class IV in one patient (7%) after 40 months mean follow-up. DISCUSSION: Surgical resection of tubers and associated epileptogenic foci in rolandic and perirolandic cortex in children with TSC is feasible, with low neurologic morbidity, and yields good seizure control. These results suggest that tubers and perituberal epileptogenic foci can be safely resected even in eloquent regions because of reorganization of functional cortex or because these lesions contain no neurologic function.