Magnetoencephalography and magnetic source imaging studies for epilepsy associated with Sturge-Weber syndrome

Abstract

Objective To study the characteristics, influence factor and clinical value of magnetoencephalography (MEG)in patients of epilepsy associated with Sturge-Weber syndrome. Methods A retrospective study was conducted at Magnetoencephalography Laboratory of Sanbo Brain Hospital, Capital Medical University. Fourteen patients of epilepsy associated with Sturge-Weber syndrome were enrolled into the study between October 2010 and June 2016. The following data were analyzed including the results of MEG with Long-term video-EEG (scalp) monitoring and preoperative MRI in all patients. Results In 8 out of 14 cases, the background activities of MEG were weakened. Epileptiform discharges were detected in 11 cases including 9 cases with epileptogenic zone on ipsilateral side of intracranial lesion (angioma, 6 cases on the right side and 3 cases on the left side) and 2 cases with bilateral epileptogenic zones. Both interictal EEG and MEG detected epileptiform discharges in 9 out of 14 cases. Epileptiform discharges were observed in 2 cases by MEG only and in 1 case by EEG only. Neither MEG or EEG detected any epileptiform discharges in 2 cases. Conclusions The interictal results of MEG seem similar to those of EEG in cases of Sturge-Weber syndrome, which mainly include weakening of background activities and epileptiform discharges commonly on ipsilateral side of brain lesion and rarely on both sides or contralateral hemisphere. The magnetic source imaging technology combining MEG and MRI could help localize the epileptogenic zone in Sturge-Weber syndrome. Key words: Sturge-Weber syndrome; Epilepsy; Magnetoencephalography; Magnetic source imaging