Abstracts

Rationale: It is established that temporal lobe epilepsy surgery is effective to reduce or eliminate seizures in almost two thirds of drug resistant patients. Despite of the debates around this subject, little information is available regarding the best way to perform antiepileptic drug (AED) withdrawal in those patients who become seizure free after surgery. A protocol of drug withdrawal was applied in patients after two years of follow up and data are presented and discussed. Methods: Patients with clinically intractable temporal lobe epilepsy (TLE) submitted to surgical treatment who became seizure free for a period of two years and had serial EEG exams without epileptic discharges were candidates to be submitted to the protocol of AED withdrawal. Patients and their families were informed about the risks and got into the protocol after informed consent. At first step we took off benzodiazepines, followed by AED which were not considered first choice for clinical treatment of TLE, and finally AED that were first choice for TLE, such as carbamazepine, oxcarbazepine and phenytoin. The withdrawal was performed gradually and the drug was reduced 25% of the total dose in a period of five half-lives of the drug. After each step the EEG was repeated. In patients whose EEG showed epileptic discharges the withdrawal was stopped and in those whose seizures recovered the AED were re-introduced integrally. Patients were followed and analyzed prospectively for a mean period of five years (range 0.5 to 10 years). Between 2002 and 2010, 280 surgeries were performed in our hospital. From them, 240 were performed to treat temporal lobe epilepsy. One hundred and seventy patiens were considered Engel 1, and 68 of them were considered Engel 1a, 48 engel 1c and 8 engel 1d. Sixty four patients consented the withdrawal, 54 were submitted to anterior temporal lobectomy (ATL), six to ATL plus lesionectomy, one to selective amygdalohippocampectomy and three to lesionectomy alone Results: In the last follow up, 37 (57,81%) were seizure free without AED; 4 (6,25%) the withdrawal was interrupted because epileptic discharges appeared in EEG and in 23 (35,94%) seizures occurred (Table1). In the latter group, 21 (32,81%) reached seizure control after reintroduction of AED and in 2 seizures were frequent despite the use of AED Conclusions: Our results to withdraw medication after temporal lobe resections are similar to other series. Our protocol seems to be safe, with high index of seizures recurrence, but when the anti epileptic drugs were fully took back, the great majority of them became seizure free again. The efficacy was significant, with almost two thirds of patients submitted to our protocol of anti epileptic drugs withdrawal, fully or partially reduced medication.