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 1,2. 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 2,3. 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 4 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 two years (range 0.5 to 4 years). Forty patients were included, 32 were submitted to anterior temporal lobectomy (ATL), four to ATL plus lesionectomy, one to selective amygdalohippocampectomy and three to lesionectomy alone (Table 1). Results: In the last follow up, 20 (50.0%) were seizure free without AED; 5 (12.5%) were tapering medication; 4 (10.0%) the withdrawal was interrupted because epileptic discharges appeared in EEG and in 11 (27.5%) seizures occurred (Table1). In the latter group, 10 (25.0%) reached seizure control after reintroduction of AED and in 1 seizures were frequent despite the use of AED. Conclusions: Our results are compatible with data available in literature 1,2,3,4 representing a safety protocol since from the 40 patients included, 72.5% did not have seizure recurrence, and 50.0% are seizure free without medication. Finally, after seizure recurrence only 9.0% showed refractoriness.