Prognostic factors for surgery of neocortical temporal lobe epilepsy

Objectives: In the current classification of epilepsies two forms of temporal Lobe epilepsy (TLE) were included: mesial and lateral (neocortical) TLE. We aimed at identifying prognostic factors for the surgical outcome of lesional neocortical TLE. Methods: We included consecutive patients who had undergone presurgical evaluation including ictal. video-EEG and high-resolution MRI, who had TLE due to neocortical lateral epileptogenic lesions, who had a lesionectomy and who had > 2-year follow-up. Results: There were 29 patients who met the inclusion criteria. Twenty of them became postoperatively seizure-free. Patients' mean age was 34.8 +/- 9 years (range 18-52). The age at epilepsy onset was 20.1 +/- 8 years. We found that left-sided surgery (p = 0.048) and focal cortical dysplasia (FCD) on MRI (p = 0.005) were associated with non-seizure-free outcome, while lateralized/localized EEG seizure pattern (p = 0.032), tumors on the MRI (p = 0.013), and a favorable seizure situation at the 6-month postoperative evaluation were associated with 2-year postoperative seizure-freedom (p < 0.001). Multivariate analysis indicated that the side of surgery was not an independent predictor. Conclusion: More than two-thirds of the patients with neocortical TLE became seizure-free postoperatively. Lateralized/localized EEG seizure pattern and tumors on the MRI were associated with postoperative seizure-freedom, while FCD were associated with a poor outcome. The 6-month postoperative outcome is a reliable predictor for the tong-term outcome. (c) 2006 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.