FEASIBILITY STUDY OF A BAR DECTECTOR SYSTEM FOR SPECT I

随着新的放射性药物示踪剂变得可用于 脑灌注和脑中的受体系统，单个 光子发射计算机断层扫描（SPECT）有望 在精神病学上有很多潜在的应用 精神分裂症 研究，在测试特定的 互相关区域异常假说 解剖（CT、MRI）和功能（PET、SPECT）检查结果 成像技术。 然而，目前的SPECT成像 系统不具有用于这种类型的工作的足够性能。 我们最近设计了一个高性能的SPECT系统， 脑功能成像，目前正在评估 这种方法的可行性和实现我们的潜力， 理论上估计的成像性能。 但这 设计仅用于单层成像。 由于每次SPECT成像 程序需要很长时间才能采集，多层成像 减少成像时间的能力对于任何实际的 临床SPECT系统。 SPECT设计的当前方向认为， 多层成像的理想形式是沿着连续采样 用于体积成像的轴向方向。 这种连续的体积 采样可以同时提供多个切片 并且还允许灵活地选择切片的位置 通过重建软件。 为了将我们提出的单层环形SPECT系统扩展到 在三维空间中，我们可以将单个的小晶体 带有位置敏感杆检测器的检测器，杆检测器的长轴 以获得轴向信息 (Z)方向 由于成本的考虑和小的宽度， 条检测器，我们建议光电倍增管（PMT）是 在几个相邻的条形探测器之间共享。 常规愤怒 位置逻辑或类似的数字位置感测方案可以 适于导出能量和位置信号。 这项拟议的试验性研究是为了确定使用 小型条形探测器和中型光电倍增管，排列在一个特殊的 模式，并由多个酒吧探测器共享，以提供足够的 用于脑的SPECT体积成像的能量和位置信号。

As new radiopharmaceutical tracers are becoming available for cerebral perfusion and receptor systems in the brain, single photon emission computed tomography (SPECT) promises to have many potential applications in psychiatry. In schizophrenia research, much work is needed in the testing of specific hypotheses about regional abnormalities in cross-correlating findings from anatomic (CT, MRI) and functional (PET, SPECT) imaging techniques. However, the current SPECT imaging systems do not have adequate performance for this type of work. We have recently designed a high performance SPECT system for functional imaging of the brain and are currently evaluating the feasibility of this approach and the potential to achieve our theoretically estimated imaging performance. However, this design is for single slice imaging only. Since each SPECT imaging procedure takes a long time to acquire, multislice imaging capability to reduce imaging time is essential to any practical clinical SPECT system. The current direction in SPECT design holds that the most desirable form of multislice imaging is continuous sampling along the axial direction for volume imaging. This continuous volume sampling may provide multiple slices simultaneously over the brain and also allow the selection of the slices' position flexibly through reconstruction software. To extend our proposed single slice ring SPECT system to the third dimension, we can replace the individual small crystal detector with a position sensitive bar detector with its long axis oriented in the 3rd dimension to obtain information in the axial (Z) direction. Due to cost considerations and the small width of the bar detector, we propose that photomultiplier tubes (PMTs) be shared among several adjacent bar detectors. Conventional Anger position logic or similar digital position sensing schemes can be adapted to derive the energy and position signals. This proposed pilot study is to determine the feasibility of using small bar detectors and medium-size PMTs, arranged in a special pattern and shared by multiple bar detectors, to provide adequate energy and position signal for SPECT volume imaging of the brain.