A PET Monte Carlo simulator from numerical phantom: validation against the EXACT ECAT HR+ scanner

The authors have developed a Monte Carlo simulator that uses realistic phantoms defined by the mean of 3D arrays. One array represents the spatial distribution of the tracer while another defines the attenuating media locations. The simulator allows the user to set the scanner geometric configuration and the acquisitions parameters. Also, effects that degrade the images which are taken into account are the poissonian emission of the positron, its positron range in the tissue, the small noncolinearity of the emitted 511 keV photon pair and the interactions that may occur at this energy range (Photo-electric, Compton and Rayleigh) in the tissue and in the detection system. Here, the authors present the features of their algorithm and its capacity to reproduce the HR+ 3D PET behavior in terms of spatial resolution and scatter distribution (most of the measurements were made according to the NEMA protocol). The simulated data are found to be in good agreement with actual data.