From the American Epilepsy Society 2009 Annual CourseMagnetoencephalography adds to the surgical evaluation process

Summarizing the podium discussion at the AES 2009, strengths and limitations of magnetoencephalography (MEG) are discussed with regard to basic methodological and clinical aspects in routine screening and presurgical evaluation of patients with epilepsies. Current literature and example cases are used to illustrate MEG contribution to clinical decision making, specifically whether a patient with pharmacoresistant epilepsy can move forward to epilepsy surgery. The main conclusion is that the largest role of MEG, as presently performed in the clinical environment, is to increase the number of patients who can go on to surgery, while it should not be used to deny surgery to any patient.

Research highlights► MEG provides non-redundant information compared to EEG for detection of epileptic activity. ► MEG is insensitive to volume conductivity differences, yielding undistorted information. ► MEG enables both focus localization and functional mapping. ► Conducting a randomized clinical trial is difficult due to ethical and practical reasons. ► Largest role for MEG is to increase the number of surgery patients.