The application of magnetoencephalography in presurgical evaluation of insular lobe epilepsy: eight cases report and review of literature

Abstract

Objective To evaluate the diagnostic value of magnetoencephalography (MEG) in localizing the seizure focus and in predicting outcome to surgical resections of insular lobe epilepsy.  Methods Eight patients who had been diagnosed as refractory insular lobe epilepsy in Xuanwu Hospital were selected. All patients had pre-surgical work-ups, including MRI, video EEG (VEEG) and MEG to localize epileptogenic area, and 4 of them had been implanted intracranial electrodes to identify epileptogenic zone and underwent operation under the monitoring of electrocorticography (ECoG). They were followed up after surgery to evaluate the prognosis, and further to evaluate the diagnostic value of MEG on insular lobe epilepsy.  Results Eight patients had surgeries under the guide of preoperative MEG examination. Five of them had been localized in insular or anterior insular lobe and 3 of them had been localized around the insular lesion by MEG. According to postoperative Engel  classification, 6 was Ⅰ, one was Ⅱ, and one was Ⅳ.  Conclusions MEG provides useful localizing information and predicts surgical outcome of insular lobe epilepsy.

doi: 10.3969/j.issn.1672-6731.2014.11.011