implementation of the wobbling technique with spatial resolution enhancement approach in the xtrim-pet preclinical scanner: monte carlo simulation and performance evaluation

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 wobbling technique offers a substantial enhancement in spatial resolution for preclinical pet scanners. although achieving sub-micrometer spatial resolutions theoretically seems feasible by increasing the number of stopping points, practical limitations present challenges. nonetheless, the wobbling technique shows promise, providing an approximate 50% improvement in spatial resolution.