[Surgical treatment of epilepsy]

The indications of surgery for epilepsy are: 1) resistance to medical treatment; 2) well-localized cortical focus, and 3) possibility of removing the focus without creating a significant functional deficit. Presurgical evaluation is initially clinical: correlations between the clinical manifestations recorded on videotapes and EEG tracings, neurological and neuropsychological examinations, intra-carotid amytal test. Interictal and, preferably, ictal EEG recording on the scalp and in depth is the fundamental procedure used to locate epileptogenic areas. The most reliable locating examination is the recording of a spontaneous seizure by means of implanted electrodes. Recent or old lesions responsible for epilepsy can be detected by arteriography, ventriculography, CT scans and, more recently, nuclear magnetic resonance. PET scan and SPECT are not commonly used. The ideal operation is cortectomy which gives the best long-term results (87 p. 100 in temporal lobe epilepsy). When cortectomy is not feasible, complete or partial (anterior two-thirds) callosotomy can be of considerable help in some forms of epilepsy with frequent falls and generalized seizures. On the whole, it seems that the surgical treatment of epilepsy is grossly underused.