Alireza Sadremomtaz, - Full professor, Department of Physics, Faculty of Science, University of Guilan, Rasht, Iran
Maziyar Mohammadi Ghalebin - PhD Student, Nuclear Physics, Department of Physics, University of Guilan, Rasht, Iran

Background: Improving the quality of images obtained by positron emission tomography (PET) imaging in nuclear medicine is of interest to researchers. The evaluation of the efficiency of PET systems is performed by identifying parameters such as sensitivity, spatial resolution, and so on. Many studies have been carried out on the use of two-layer crystalline detectors, different from scintillating materials.Methods: In this research, using a Monte Carlo Simulation (GATE), an Animal PET imaging device with variable crystal was simulated. For this device, by varying the scintillating materials of the detectors, parameters of the sensitivity and spatial resolution of the reconstructed in the radial direction for the source in the center were calculated and compared to provide scintillations that are more efficient. In this simulation for the two-layer mode, LYSO-GSO, LuAP-BGO, YAP-BGO, LPS-BGO, LSO-GSO were used.Results: After evaluating the accuracy of the program s performance, the sensitivity results for the above states were 2.50%, 5.72%, 3.0%, 4.83%, 4.30%, respectively. The spatial resolution of the radial direction for the above states was 1.24, 1.80, 3.49, 1.86, and 2.25 mm, respectively. Conclusion: The results show that the LuAP-BGO mode has a higher sensitivity and LYSO-GSO mode with better spatial resolution. Considering the sensitivity and spatial resolution results, a better mid-range should be considered for better crystal selection.

Animal PET, Scintillating, Sensitivity, Spatial resolution