Abstracts

Rationale: Published outcome data for older patients undergoing epilepsy surgery is limited and shows variable results. In this study, retrospective data was collected from 52 epilepsy surgery patients, including both temporal and extra-temporal resections. Seizure outcome and neuropsychological testing data was compared between older and younger groups. The disparity we found between the older and younger groups was greater in our data sample than in previous reports. Methods: Patients were included in the study if they were over 18 years old at the time of surgery, underwent epilepsy surgery since the year 2000, completed both preoperative and postoperative neuropsychological testing, and had follow-up clinic visits documenting seizure outcome information. We compared seizure outcome and neuropsychological testing data between two patient groups defined by age >40 (N=23) and age <40 (N=29) at time of surgery using Chi Square tests. Results: The mean age of the older group was 49.3 years with mean epilepsy duration of 25.3 years. The younger group had a mean age of 29.2 years with a mean duration of epilepsy of 17.7 years. The mean postoperative follow-up period was 2 years, which did not differ between groups. Ten (43%) of the older patients had an Engel class I outcome compared to 24 (83%) of the younger patients which was statistically significant (p<0.01 using Chi square test). Neuropsychological testing was done a mean of 8.9 months after surgery and compared with preoperative data. Twelve (52%) of the older patients had a decline compared to seven (24%) of the younger patients (p<0.05 using Chi square test). Conclusions: The percentage of older patients who achieved seizure freedom was significantly less than the younger patients. The percentage of older patients who had notable neuropsychological decline was also significantly higher than in the younger patients. Although a majority of patients in both groups had a significant seizure reduction, the counseling of older patients in regards to the potential outcome of surgery may need to be adjusted.