Implementation of a single scatter simulation algorithm for 3D PET: application to emission and transmission scanning

We describe a new implementation of a Single Scatter Simulation (SSS) algorithm for the prediction and correction of scatter in 3D PET. Comparison of SSS predictions to Monte Carlo simulations and experimental data from uniform, line and cold-bar phantoms showed that the code is accurate for uniform as well as asymmetric objects and can model different energy-resolution crystals and low level discriminator (LLD) settings. The method was also extended to the case of transmission scanning and applied to patient studies. Ongoing work aims at incorporating the algorithm in routine clinical image reconstruction, at evaluating its accuracy in absolute quantitation studies, and its robustness in the case of large patients, where the scatter fraction increases.