Anti-Epileptic Drug Withdrawal after Surgery for Focal Cortical Dysplasia (P2.049)

OBJECTIVE: To estimate the frequency of AED reduction or withdrawal after epilepsy surgery in FCD. BACKGROUND: Focal cortical dysplasia (FCD) is the most common pathology for pediatric drug-resistant focal epilepsy and accounts for a third of surgical cases in adults with focal epilepsy. Information on the likelihood of antiepileptic drug (AED) reduction or withdrawal after surgery in FCD is limited. METHODS: All patients who underwent epilepsy surgery at the Mayo Clinic Rochester between 2000 and 2012 with pathology confirmed FCD were included in this retrospective study. Epilepsy history, surgery outcome, pre- and post-operative AED treatments were analyzed. Surgical outcome was classified as favorable (Engel I and II) or not favorable (Engel III-IV). RESULTS: Sixty-three FCD cases were identified (59[percnt] male, 60[percnt] ≤18 years at time of surgery). The median AED trials prior to surgery was 6 (IQR 5-8), and median AED at time of surgery 2 (IQR 2-3). Favorable outcome was achieved in 44 patients (69[percnt]), including 34 patients (53[percnt]) with seizure free control (median follow-up 2 years, IQR 0.6-4.7 years). Outcome was not influenced by age of seizure onset, duration of epilepsy, age at surgery or number of AED trials prior to surgery. Medication reduction was undertaken in 30/44 patients (66[percnt]) with favorable outcome and was more likely with surgical intervention during childhood (75[percnt] vs. 30[percnt], p=0.0005). Among patients who were seizure free, 8/34 patients (23[percnt]) were without AED at last follow-up, all with surgical intervention during childhood. CONCLUSIONS: Surgical outcome in FCD is favorable in about 2/3 of patients, including about 50[percnt] of patients achieving seizure-free control. Medication reduction was possible in the majority of patients with favorable outcome, but attempt to withdrawal AED were less frequently pursued despite seizure free control. Disclosure: Dr. Vazquez-Figueroa has nothing to disclose. Dr. Mrelashvili has nothing to disclose. Dr. Wong-Kisiel has nothing to disclose.