[Surgically treatable epilepsy--a review]

Abstract

20-25% of epileptic patients do not become seizure free on adequate drug therapy. In 25-50% of patients with intractable epilepsy, the brain area responsible for seizures is well localizable and does not involve eloquent regions. In these patients, the surgical excision of the epileptic focus may lead to relief from seizures. In Hungary, there may be 5-6000 patients who needs an epilepsy surgery, but till now only 200 patients with chronic epilepsy underwent a surgical procedure. In the surgically remediable epilepsies, the operation is not a "ultima ratio". Concerning these syndromes, if 2-3 adequate antiepileptic drugs do not lead to seizure freedom within 1-3 years after the epilepsy onset, then a presurgical evaluation is necessary. The most common surgically remediable epilepsy is the temporal lobe epilepsy in which 60-90% of drug-resistant patients could be surgically cured. In lesional neocortical epilepsies 50-80% of patients become postoperatively seizure free. In childhood hemispheric epilepsies, the surgery could lead to seizure freedom in 70-80% of patients. The basic tools of the presurgical evaluation are the detailed history, the high resolution-MRI, the video-EEG monitoring, and the neuropsychological assessment. These investigation methods are usually enough to evaluate the necessity of the surgery and the postoperative outcome as well as to plan the localization and the extension of the resection. In some cases, ictal SPECT, PET, or video-EEG monitoring with intracranial electrodes could also be necessary in order to localize the epileptic focus.