A GENERAL TECHNIQUE FOR INTERSTUDY REGISTRATION OF MULTIFUNCTION AND MULTIMODALITY IMAGES

A technique that can register anatomic / structural brain images (e.g, , MRI) with various functional images (e.g., PET-FDG and PET-FDOPA) of the same subject has been developed. The procedure of this technique includes the following steps: 1) segmentation of MRI brain images into gray matter (GM), white matter (WM), cerebral spinal fluid (CSF), and , muscle (MS) components, 2) assignment of appropriate radiotracer con centrations to various components depending on the kind of functional image that is being registered, 3) generation of simulated functional images to have a spatial resolution that is comparable to that of the measured ones, 4) alignment of the measured functional images to the s imulated ones that are based on MRI images. A self-organization cluste ring method is used to segment the MRI images. The image alignment is based on the criterion of least squares of the pixel-by-pixel differen ces between the two sets of images that are being matched and on the P owell's algorithm for minimization. The technique was applied successf ully for registering the MRI, PET-FDG, and PET-FDOPA images. This tech nique offers a general solution to the registration of structural imag es to functional images and to the registration of different functiona l images of markedly different distributions.