Registration of EEG electrodes with three-dimensional neuroimaging using a frameless, armless stereotactic wand

A technique of image and electrode registration has been developed that allows electroencephalogram electrode location to be merged with 2-D or 3-D MRI or CT. An armless, frameless stereotactic localization system that may be used in or out of the operating room is used to generate spatial data for surface and accessible intracranial electrodes. Acquisition of electrode position data may be obtained before or after neuroimaging and the locations of additional electrodes added at any time. The methodology of this system and representative cases with MRI imaging are presented.