Reconstruction of the radiation sources distribution in the proportional scattering medium

A new method of image reconstruction for single-photon emission computer tomography (SPECT) in a proportional scattering medium has been suggested. Detector counts have been obtained by Monte Carlo simulation using the Geant4 nuclear physics software package, which has eliminated the need for applying a real tomograph, radiopharmaceuticals (radiotracers), and a SPECT phantom. Detector counts obtained using Geant4 are virtually the same as those that could be obtained in a full-scale experiment carried out in a real scattering medium. The influence of the absorbing and scattering capabilities of 13 different substances modeling a medium in which the radiation source spatial distribution is submerged on the tomogram reconstruction accuracy has been studied. That this algorithm has considerable advantages for emission tomogram reconstruction over conventional one have been demonstrated.