The role of Monte Carlo modeling in tomograph design

Monte Carlo methods have been used in almost every aspect of PET system design, such as studies of detector materials used optimisation of light collection and count rate performance studies. In the design of a new PET design, an initial Monte Carlo simulation study is almost inevitable. This will not only allow the designer to predict the performance of a particular system design without the construction of a complete system, but also guide in any adjustment in the design. An area of PET detector design that has been widely investigated in recent years, is the possibility to implement a means to determine the depth of interaction (DOI) to improve image resolution. Using the Monte Carlo technique, a complete system with a variety of system configuration could be simulated where the layer thickness were varied and different combinations of scintillator materials were used and arranged in different order. The results of these studies showed that the addition of the DOI information provided a more uniform resolution across the tomograph FOV. The most dramatic improvement was seen when the detector thickness was divided into two layers, whereas a further reduction in detector depth only provided a marginal improvement. Copyright (1999) The Australian and New Zealand Society of Nuclear Medicine Inc