Experimental comparison of relative stopping power evaluation between proton CT and x-ray CT for pre-clinical proton irradiation studies of small animals.

. Proton therapy experiments in small animals are useful not only for pre-clinical and translational studies, but also for the development of advanced technologies for high-precision proton therapy. While treatment planning for proton therapy is currently based on the stopping power of protons relative to water (i.

Pre-computed system matrix calculation based on a piece-wise method for PET.

A system matrix (SM) is the basic component of iterative image reconstruction algorithms. Calculation of the SM needs a considerable amount of time due to an enormous number of lines of response (LORs) being modeled. In this study, we developed a technique based on a piece-wise calculation method in which symmetry and further division of the voxels are applied.