Design and numerical simulations of a large animal SPECT system
ZHANG Zhihan1, LIU Hui1, L�Zhenlei1, HOU Yansong2, SUN Lifeng3, WANG Shi1, WU Zhaoxia1, LIU Yaqiang1
1. Department of Engineering Physics, Tsinghua University, Beijing 100084, China; 2. Beijing NOVEL MEDICAL Equipment Ltd., Beijing 102206, China; 3. CNNC High Energy Equipment(Tianjin) Co., Ltd., Tianjin 300300, China
Abstract：This study analyzed the collimator parameters of a large animal single photon emission computed tomography (SPECT) detector. Six collimator design schemes were chosen by thoretical calculation of the spatial resolution, the sensitivity at the field of view (FOV) center and the projection overlap ratio with specified constraints. A performance evaluation method was used to evaluate the six collimator design schemes by calculating the contrast recovery coefficient (CRC) and the variance of the local impulse response of selected pixels to find the best design scheme. The imaging effect of the design scheme was verified by numerical simulations of imaging experiments of a hotrod phantom. The theoretical calculations and the numerical simulations demonstrate that the design scheme gives a spatial resolution of the hotrod phantom that is better than 3.0 mm with better than 0.03% sensitivity at the FOV center, which meets the technical requirements.
张旨晗, 刘辉, 吕振雷, 侯岩松, 孙立风, 王石, 吴朝霞, 刘亚强. 大动物SPECT系统设计与数值模拟[J]. 清华大学学报（自然科学版）, 2022, 62(12): 1875-1883.
ZHANG Zhihan, LIU Hui, L�Zhenlei, HOU Yansong, SUN Lifeng, WANG Shi, WU Zhaoxia, LIU Yaqiang. Design and numerical simulations of a large animal SPECT system. Journal of Tsinghua University(Science and Technology), 2022, 62(12): 1875-1883.
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2022, Vol. 62 
