Abstracts

Rationale: Studies have consistently found an average time between the onset of epilepsy and epilepsy surgery of about 20 years (1,2). Emerging evidence indicate that early epilepsy surgery might prevent cognitive and psychosocial decline (3,4). The American Academy of Neurology, in association with American Epilepsy Society, and the Association of Neurological Surgeons issued a Practice Parameter in 2003 to assist physicians in clinical decision making related to the treatment of pharmacoresistant temporal lobe epilepsy. Based upon a rigorous and comprehensive evaluation, they recommended 1) that patients with disabling seizures who have failed trials of first-line anti-epileptic drugs be referred to an epilepsy surgery center and 2) that appropriate patients who accept its risks and benefits be offered surgery (2). What remains unclear is whether the average duration of epilepsy prior to epilepsy surgery has decreased since the publication of the Practice Parameter in 2003. The goal of this study is to compare the duration of epilepsy prior to temporal lobe resection among patients who had temporal lobe resection at our epilepsy center before and after the publication of the AAN Practice Parameter in 2003. Methods: Using our electronic epilepsy surgery database, we performed a retrospective review of patients who had anterior temporal lobe resections at the Columbia Comprehensive Epilepsy Center between 1996 and 2007. Patients were divided into three groups, based on the year of epilepsy surgery: group A (1996 to 1999), group B (2000 to 2003), group C (2004 to 2007). For patients that had more than one temporal lobe resection, the first surgery had to have occurred between 1996 and 2007 and duration was calculated as the difference between the onset and the first surgery. Onset age was defined as age at first non-febrile seizure. The primary study endpoint was epilepsy duration prior to temporal lobe resection, calculated as the age at epilepsy surgery minus the age of epilepsy onset. The mean duration between onset and surgery was compared among the three groups using ANOVA. Results: There were 205 patients who had temporal lobe resections between 1996 and 2007 at our center. No significant difference in mean duration was found. See table for the mean duration for all three groups. Conclusions: Mean duration of epilepsy prior to temporal lobe resection has not decreased considerably in those who had surgery after 2003 following the publication of AAN Practice Parameter, compared to those who had surgery before 2003. Further validation is needed with additional surgical cases from multiple centers from various regions.