Epilepsy surgery in a reference centre

INTRODUCTION: Patients with drug resistant epilepsy are potential candidates for surgery. The pre surgical study of these patients involves a multidisciplinary approach. PATIENTS AND METHODS: We included patients who had been submitted to EEG video monitoring in our centre (a tertiary university hospital) between April 1995 and May 2000. The evaluation protocol included magnetic resonance (MR) brain scan (according to a specific protocol), neuropsychological and psychiatric evaluation, and ictal/interictal SPECT, when possible. Patients who underwent surgery were followed up at regular intervals until at least two years after surgery. RESULTS: Of the 299 patients with EEG video monitoring, 87 had been submitted to surgery up to June 2000. Nine of these patients required invasive subdural studies or studies of the foramen ovale using electrodes. Of the patients who underwent surgery, 44.8% had sclerosis of the hippocampus in the MR and in 10% it was found to be normal. The results of pathological anatomy revealed: 49.3% with sclerosis of the hippocampus, 15.1% with benign tumours, 13.7% with gliosis, 4.1% heterotopias and 4.1% cavernomas. Just one patient has been submitted to surgery again because of badly controlled seizures. Eight patients have presented post surgical complications (four with permanent morbidity). Of the 73 patients who were followed up for at least a year, 83.6% are in Engel class I, 9.6% in class II, 2.7% in class III and 4.1% in class IV. Among patients who underwent a temporal resection, 88.7% were in class I and 0% in class IV. CONCLUSIONS: Epilepsy surgery, in selected patients, has a very low morbidity/mortality rate and the chances that seizures will disappear or greatly improve are high.