Levetiracetam efficacy in refractory partial-onset seizures, especially after failed epilepsy surgery

Purpose: We conducted a retrospective study to evaluate the efficacy of levetiracetam as adjunctive therapy in patients with localization-related epilepsy, and specifically in the subset of patients for whom epilepsy surgery failed. Methods: Eighty-two patients with uncontrolled partial-onset seizures treated with levetiracetam were identified; epilepsy surgery had failed for 21 (25.6%; group I), and 61 (74.4%) had no prior surgery (group II). Group I and group H patients were comparable in age (mean, 40.7 vs. 41.5 years) and age at seizure onset (mean, 14.4 vs. 18.2 years). Patients-who had greater than or equal to50% reduction in seizure frequency were considered responders; the remaining patients were considered nonresponders. Results: In patients (group I) for whom surgery had failed, responder rate was 76.1% (16 of 21), including 10 (47.6%) patients who became seizure free. In nonsurgical patients (group II), responder rate was 34.3% (21 of 61), including nine (14.7%) patients who became seizure free. In group I, II (91.6%) of 12 temporal resection patients were responders, of whom eight were seizure free; of the remaining nine operated (extratemporal) patients, five (55.5%) were responders, and two were seizure free. In three responders, all in group I, a severe, delayed psychotic syndrome developed 4 to 9 months after levetiracetam introduction, leading to its discontinuation. Conclusions: These findings suggest that adjunctive levetiracetarn therapy should be considered early after failed epilepsy surgery, especially after temporal resection, and may have implications for its use before surgical intervention. Patients should be under close psychiatric observation in this clinical setting.