Clinical Research Epilepsy Surgery in Children with Tuberous Sclerosis Complex: Presurgical Evaluation and Outcome

Summary: Purpose: Children with tuberous sclerosis com- plex (TSC) benefit from excisional surgery if seizures can be localized to a single tuber. We evaluated the role of noninva- sive studies to localize the epileptogenic tuberhegion (ET/R) and the outcome of focal resection. Methods: We identified 21 children with TSC, ages 3 months to 15 years (mean 4.8 years). All had video-(electro- encephalogram) EEG and magnetic resonance imaging (MRI) scans, and 18 also had ictal single photon emission-computed tomography (SPECT) studies. An ET/R was localized in 17 patients. Thirteen patients underwent resection guided by in- traoperative electrocorticography (n = 7) or subdural monitor- ing (n = 6). Results: Interictal EEG revealed a principal spike focus (PSF) that corresponded to the ET/R in 14 children. In seven, PSFs occurred in rhythmic runs. PSFs were not observed re- mote from the ET/R. Focal polymorphic slowing and attenua- tion occurred in the region of the PSF in 1 I patients. Sixteen patients demonstrated an ictal focus corresponding to the ET/R. Ictal SPECT revealed focal hyperperfusion correlating with the ET/R in 10 patients. Although the MRIs in all children revealed multiple tubers, the ETR corresponded to a large discrete tuber in 8 patients and a calcified tuber in 13 patients. Patchy calci- fied tubers were also seen elsewhere in six patients. At a mean follow-up of 26 months, 9 of the 13 children who underwent surgery were seizure-free, one had greater than 75% reduction in seizures, two were unchanged, and one was lost to follow-up. New seizures developed in one child from