[Preoperative and postoperative magnetoencephalography in a patient with partial epilepsy]

Magnetoencephalography (MEG) is a non-invasive method with a potential of clinical diagnostic use to localize epileptogenic foci in the brain. The aim of this study was to investigate whether the pathological focus localized by MEG was concurrent with the conventional preoperative examinations in a patient with medically intractable epilepsy who underwent surgery (left side uncohippocampectomy). A conventional preoperative test battery had already documented a left-hemisphere fronto-temporal epileptogenic focus. Postoperatively the patient was seizure free. MEG was performed three months before and ten months after the operation. The analysis of the MEG data indicated a left hemisphere fronto-temporal focus in agreement with results obtained by means of the conventional methods used for locating epileptic foci. Postoperatively the focus had disappeared.