Pet image reconstruction with on-the-Fly Monte Carlo using GPU - 213

Particle transport Monte Carlo is an inherently parallel algorithm and with all the further similarities to visible light ray-tracing it can easily be realized on current Graphics Processing Units (GPUs). This paper describes a GPU-based gamma photon transport code with application to the iterative image reconstruction steps of Positron Emission Tomography. The aim of the investigations here is the development of a Monte Carlo code capable of calculating the forward projection of each iteration step in the reconstruction with calculation times on the minute scale. Achieved simulation speed is in the order of 108 positrons per second. (authors)