Tehran University of Medical Sciences Frontiers in Biomedical Technologies 2345-5837 12 2 2025 03 01 387 398 Bahador Bahadorzadeh Nuclear Engineering Department, School of Mechanical Engineering, Faculty of Engineering, Shiraz University, Shiraz, Iran Reza Faghihi Nuclear Engineering Department, School of Mechanical Engineering, Faculty of Engineering, Shiraz University, Shiraz, Iran Sedigheh Sina Nuclear Engineering Department, School of Mechanical Engineering, Faculty of Engineering, Shiraz University, Shiraz, Iran Ahdiyeh Aghaz Radiation Application Research School, Nuclear Science and Technology Research Institute, Tehran, Iran Arman Rahmim Nuclear Engineering Department, School of Mechanical Engineering, Faculty of Engineering, Shiraz University, Shiraz, Iran Mohammad Reza Ay Department of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran 2023 09 24 2023 12 02 Purpose: The Xtrim-PET preclinical scanner is specifically designed for positron emission tomography (PET) imaging of small laboratory animals. This study aims to increase the spatial resolution of the scanner by implementing gantry wobbling. Materials and Methods: The gantry wobbling was evaluated using the Gate Monte Carlo code. To prevent image blurring during gantry wobbling, all locations detected in the 3D output were corrected in the sinogram matrix according to the coincidence time of annihilation photons and the gantry motion. In order to evaluate the performance of the scanner using the wobbling motion data acquisition technique, coincidence data from the scanning of NEMA-NU4 and Hot-Rod phantoms were modified, reconstructed and compared to without wobbling mode. Results: The spatial resolution in the center of the scanner with and without implementing wobbling technique was obtained as 0.91 mm and 1.93 mm, respectively. The total sensitivity, detection efficiency, and scan time were obtained the same in both with and without wobbling modes. The results indicate that the data acquisition mode with gantry wobbling motion increases the resolution up to 52.8% Conclusion: The proposed data acquisition mode can be used to design a cost-effective high-resolution scanner. https://fbt.tums.ac.ir/index.php/fbt/article/view/833 https://fbt.tums.ac.ir/index.php/fbt/article/download/833/397