ITERATIVE RECONSTRUCTION OF PET IMAGES USING A HIGH-OVERRELAXATION SINGLE-PROJECTION ALGORITHM

An iterative image reconstruction procedure is described which is able to calculate high-precision images within eight iterative steps. High initial overrelaxation parameters are used which drop down towards ab out one during continuing iteration. The parameters are determined pra gmatically, postulating maximum gain of image quality during a sequenc e of iterative steps. Results with simulated and measured data show th at parameters derived from one data set may be widely used for other d ata sets. The acceleration of iterative reconstruction achieved by the estimation of optimum overrelaxation parameters is important for larg e data sets, especially for fully 3D reconstruction.