“…Virtually, any complex system can in principle be modeled: if the distribution of events that occur in a system is know from experience, a PDF can be generated and sampled randomly to simulate the real system. A detailed description of the general principles and applications of the Monte Carlo method can be found elsewhere: (Andreo, 1991;Zaidi, 1999;Ljungberg, 1998Ljungberg, , 2004Zaidi & Sgouros, 2002;Zaidi, 2006). The simulation of PET imaging using Monte Carlo allows the optimization of system design for new scanners, the study of factors affecting image quality, the validation of correction methodologies for effects such as scatter, attenuation and partial volume, for improved image quantification, as well as the development and testing of new image reconstruction algorithms.…”