Abstracts

Rationale: Surgery is an effective option for medically refractory localization-related epilepsy and the one-year seizure outcome is most predictive for long-term seizure control. In this study, one-year seizure outcomes were reviewed for patients evaluated and treated at the South Texas Comprehensive Epilepsy Center (STCEC). Methods: This retrospective analysis included patients undergoing epilepsy surgery at the STCEC in San Antonio, Texas. Preoperative evaluation included video-electroencephalography, MRI of the brain, neuropsychological testing, interictal PET or interictal/ictal SPECT scans and intracarotid amobarbital testing. The epilepsy surgery database at the STCEC included 156 patients who underwent resections between Novemeber 1995 and February 2006. All patients had at minimum monthly seizures and failed at least 2 antiepileptic medications. Twenty-four patients were excluded because of incomplete medical records, inability to appear for one-year follow-up visit, or because of repeat surgeries. Seizure outcome was categorized based on the modified Engel classification system. Results: Of the 132 patients, 105 (80%) underwent temporal lobe and 27 (20%) underwent extra-temporal resections. Sixty-eight resections were left hemispheric and sixty-four were right hemispheric. Sixty-nine (52%) were female. The age range at surgery was 16 months to 59 (mean 32 years) years old. Ninety-one percent of temporal resections had underlying lesions (including hippocampal sclerosis) compared to 74% of the extratemporal cases. The rate of complete postoperative seizure freedom (Class I) at 1 year was 53% for temporal lobe resection and 52% for extratemporal resection, while poor outcomes (Class IV) were seen in 22% of extra-temporal lobe resections compared to 8% of temporal lobe resections. Of the patients with Class I outcomes, lesions were apparent in 92% of temporal lobe resections and 82% of extratemporal resections. Conclusions: The one-year seizure outcomes in this cohort were similar to those quoted by other epilepsy surgery centers. Good surgical outcomes (Class I and II) were evident in 82% of the temporal lobe resections and 63% of the extratemporal surgeries. Surgeries in lesional cases appear to be successful regardless of their location, though a selection bias needs to be considered.