Improved list-mode reconstruction with an Area-Simulating-Volume projector in 3D PET

In this paper, a new forward/backward projector-Area-Simulating-Volume (ASV) is proposed to improve image quality in 3D list-mode (LM) PET reconstruction. This algorithm calculates the overlapping area between the tube-of-response (TOR) and image voxel by the product of two distance ratios in the X-Y plane and Y-Z (or X-Z) plane, and applies this area as the geometric probability in the system matrix. The ASV method outperforms a widely used ray tracing method in terms of image quality and convergent rate, which has been verified through Monte Carlo simulations and a phantom experiment.