Analysis of reoperation of 12 patients with temporal lobe epilepsy and mesial temporal lobe sclerosis

Incomplete resection of mesial temporal lobe structures entails reoperation in a small number of patients with mesial temporal sclerosis (MTS) who had no satisfactory outcome after in-itial surgery for temporal lobe epilepsy (TLE). We analyzed 12 consecutive patients with MTS (follow-up 14 to 71 months, mean 42.4) by evaluating noninvasive EEG/ video monitoring before the first and second surgery (interictal epileptiform discharges -IED, ictal EEG, semiology) and MRI (resection index after the first and second surgery of amygdala, hippocampus, lateral temporal lobe). Five of 12 patients became seizure free. Recurrence of seizures could be predicted by: 1) ictal EEG with propagation to the contralateral temporal lobe (0 of 5 patients seizure free versus 5 of 7 patients; p=0.028); 2) quantity of lateral temporal lobe resection in the second surgery (1.06 +/- 0.59 cm versus 2.18 +/- 1.37 cm; p=0.037). No significant correlation was found for lateralization of IED, change of semiology, other resection indices, begin and duration of epilepsy, duration of follow-up, and side of surgery. Patients have a less favorable outcome if they show ictal scalp EEG with contralateral propagation and if they had already undergone an extended first resection of the lateral temporal lobe.