A new method for the correction of gamma camera nonuniformity due to spatial distortion

A methodology for correcting scintillation camera nonuniformity resulting from spatial linearity distortion is described. The method simultaneously corrects for both variations in count density and distortions in spatial linearity without altering the intrinsic sensitivity or resolution of the imaging system. This approach to linearity correction requires only a single flood image from which the spatial shift vectors are derived. The algorithm has been implemented on a PC-based, EISA bus microcomputer, and reduces the measurement of integral uniformity for 201Tl from 25% to 5%. Combined with regional correction for photopeak pulse-heights shifts (i.e. energy correction), the algorithm represents a novel technique for implementing uniformity correction completely within software.