AUTOMATIC CO-REGISTRATION OF MEG AND 3D DIGITIZATION USING 3D GENERALIZED HOUGH TRANSFORM

In this study, we propose a new automatic co-registration method for the coordinate systems of magnetoencephalography (MEG) data and third dimension digitizer (3D DIG) data of a head using the 3D generalized Hough transform (GHT) during image processing. The technique is important for the research of brain functionalities; it can be done automatically, and quickly combines data from functional brain mapping tools like MEG and DIG, etc. MEG is a measurement instrument used to noninvasively analyze the physiological activity of neurons with high temporal resolution, but it lacks the head-shape of subjects and head with respect to the MEG sensors. 3D DIG can record head-shape, facial features, and anatomical markers in a 3D coordinate system in real time. Thus, combining the two modalities is beneficial in correlating the obtained brain data with physiological activity. According to much of the research, the GHT is useful for recognizing or locating two 2D images. However, the GHT algorithm can be extended to the 3D GHT to automatically co-register the 3D data. In this study, we use the 3D GHT to co-register three subject datasets with MEG and 3D DIG data, and evaluate the average distance errors between the proposed method and the MEG160 system. Some of the experimental results demonstrate the applicability of the proposed 3D GHT accurately and efficiently.