Graphics Hardware Accelerated Reconstruction of SPECT with a Slat Collimated Strip Detector

3D iterative reconstruction of Single Photon Emission Computed Tomography (SPECT) acquisitions is a widely used but computationaly intensive process. Reconstructing data from a rotating slat collimated system increases the computation time even further. Since the sensitivity profile of such a camera is not constant over the field of view, it is important to include a system model that is as accurate as possible. We derived a Monte Carlo model of the physics of the measurement process. The advances in programmable graphics hardware make it possible to efficiently model the 3D reconstruction algorithm on consumer grade graphics cards in order to reduce the computation time. This paper describes an implementation of the reconstruction algorithm which is as accurate as the software algorithm while still achieving a 10-fold speed increase over the optimized software version.