A NEW METHOD FOR THE CORRECTION OF GAMMA-CAMERA NONUNIFORMITY DUE TO SPATIAL DISTORTION

A methodology for correcting scintillation camera nonuniformity result ing from spatial linearity distortion is described. The method simulta neously corrects for both variations in count density and distortions in spatial linearity without altering the intrinsic sensitivity or res olution of the imaging system. This approach to linearity correction r equires only a single hood image from which the spatial shift vectors are derived. The algorithm has been implemented on a PC-based, EISA bu s microcomputer, and reduces the measurement of integral uniformity fo r Tl-201 from 25% to 5%. Combined with regional correction for photope ak pulse-height shifts (i.e. energy correction), the algorithm represe nts a novel technique for implementing uniformity correction completel y within software.