A new approach to three-dimensional image reconstruction in PET

A novel method for 3-D image reconstruction in PET (positron emission tomography) that preserves the simplicity of the 2-D methods was developed. It was primarily developed for a PET system consisting of two rotating scintillation cameras with a restricted axial field of view. In principle, however, it can also be used for multiring cameras with the interplane septa removed. The basic principle of the method is to organize the projection data so that 2-D reconstruction can be used. The method consists of a combination of analytical and algebraic algorithms, including an iterative process with 2-D reconstruction of transaxial slices and deconvolution of a position-dependent axial spread function. With this method one avoids the complex and time-consuming operation of 3-D backprojection, but can still utilize all the detected events and take advantage of the 3-D information. The method has been evaluated with Monte Carlo simulations and phantom measurements.<>