Magnetoencephalography: clinical application in epilepsy.

Magnetoencephalography (MEG) has developed to the point that it has now entered routine clinical application. Epilepsy MEG studies show that it can accurately localize spike sources--both ictal and interictal--as compared with both directly. Limitations involve difficulties in detecting complex or deep sources when recording spontaneous cerebral activity. MEG not only provides a novel tool to localize and characterize epileptiform disturbances, it also has an important role in determining the significance of abnormalities seen on both structural and functional imaging. Ultimately, MEG should play a major role in totally noninvasive epilepsy surgery evaluation.