高分辨率小动物SPECT成像系统的设计与性能评估  

Design and Performance Evaluation of High-Resolution Small Animal SPECT System

作　　者：戴甜甜[1] 刘亚强[1] 马天予[1] 夏彦[1] 王石[1] 魏清阳[1] 金永杰[1] 

机构地区：[1]清华大学工程物理系粒子技术与辐射成像教育部重点实验室,北京100084

出　　处：《原子能科学技术》2011年第3期369-373,共5页Atomic Energy Science and Technology

基　　金：教育部博士点基金资助项目(200800031071);国家自然科学基金资助项目(10975086);国家863计划资助项目(2006AA020802)

摘　　要：为实现低成本、高分辨率的小动物单光子发射断层成像(SPECT),设计了一种基于临床探测器和针孔准直器的小动物SPECT成像系统。综合考虑视野尺寸、空间分辨率和绝对探测效率等指标,分别给出了单针孔和七针孔准直器的两种最优化设计方案,并通过对比两种设计方案在全视野范围内的平均空间分辨率和探测效率,对成像性能进行了评估。结果表明,与单孔准直器相比采用七针孔准直器设计可同时获得更高的空间分辨率和探测效率。经蒙特卡罗模拟成像实验验证,该七针孔准直器在临床探测器上可达0.5mm级的超高空间分辨率,且成本远低于采用专用探测器的现有小动物SPECT系统。A high-resolution and low-cost small animal single photon emission computed tomography（SPECT） system was designed based on a clinical scanner and a pinhole collimator.Optimal design schemes of a single-pinhole collimator and a seven-pinhole one were proposed,in terms of achieving the best trade-off of field of view size,spatial resolution and sensitivity.System performances of the two design schemes were compared by evaluating the average spatial resolution and sensitivity over the full field of view,and the seven-pinhole collimator design demonstrated improved resolution and better sensitivity.Monte Carlo simulation studies validate that ultra-high 0.5 mm spatial resolution can be achieved with the proposed seven-pinhole design,which is cost-effective comparing to the existing animal SPECT systems equipped with dedicated detector.

关 键 词：单光子发射断层成像 小动物成像 针孔准直器 空间分辨率 探测效率 蒙特卡罗模拟 

分 类 号：R445.6[医药卫生—影像医学与核医学]