Integration of EEG and SPECT data acquired from simultaneous examinations

The aim of this study was to develop a convenient method for superimposing SPECT images and EEG maps. This work was performed as part of research concerning feasibility of improving the localization of epileptic foci comparing to the standard SPECT examination by applying the technique of EEG mapping. The described method relies on making five EEG electrodes visible in SPECT images, calculating the coordinates of these electrodes in SPECT image space, approximating the coordinates of the remaining electrodes used in EEG recording and then computing a sequence of 3D EEG maps spanning on all the electrodes. An example of visualization of EEG and SPECT data integration was presented. The maximum error of the five base electrodes location was assessed below 10 mm. Assuming the exact placement of the base electrodes the accuracy of the proposed method was estimated below 5.5 mm.