RT Journal Article SR Electronic T1 Anatomic localization of cerebral cortical function by magnetoencephalography combined with MR imaging and CT. JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology SP 713 OP 716 VO 11 IS 4 A1 W W Orrison A1 L E Davis A1 G W Sullivan A1 F A Mettler, Jr A1 E R Flynn YR 1990 UL http://www.ajnr.org/content/11/4/713.abstract AB Magnetoencephalography (MEG) monitors magnetic field amplitudes, which are time averages of evoked neuronal responses. This method can detect magnetic fields emanating from the brain and localize the neuronal source. The location of somatosensory neuronal sources for voluntary right thumb and right index finger flexions were determined in four normal volunteers by using a seven-sensor neuromagnetometer inside a magnetically shielded room. These neuronal sources were then identified on the individual's respective CT or MR scans, and correlation was accomplished by geometric calculations, direct cranial measurement, and surface marker identification. Specific functional magnetic fields were located over the appropriate sensory motor cortex; however, there was considerable variation in the exact site. Magnetoencephalography combined with CT and MR may improve localization of normal and abnormal neurologic function.