Segmented-Parallel-Beam Stationary Cardiac SPECT

分段平行束固定式心脏SPECT 摘要： 该项目的目标是开发一种固定的心脏SPECT(单光子发射计算 使用安装在大面积NaI(Tl)探测器上的新型分段平行孔准直器)系统。 这种固定的SPECT系统建造成本低，不需要运动，并且能够获得一致的SPECT。这 系统可以获得真实的动态SPECT图像。 频谱动力学公司开发了一种用于心脏SPECT的固定伽马相机，称为D- SPECT。D-SPECT没有门架旋转，但探测器在连续扫描。因此， D-SPECT并不是一个真正固定的系统。 加州大学旧金山分校和韦斯特大学联合提出了一种真正的固定式心脏SPECT系统 心脏病协会。他们的系统是一个改进的三探测器SPECT系统，安装了三个多探测器SPECT系统 针孔准直器。他们已经使用这种装置成功地获取了心脏SPECT图像。通用电气也有 开发了一种固定式、多针孔专用心脏SPECT系统，名为Alcyone。我们建议的研究 是用我们原创设计的分段平行孔准直器取代多针孔准直器。在一个 分段平行孔准直器，整个探测区域被划分为许多较小的子区域。这个 每个节段上的准直器孔指向心脏。 我们用分段平行孔技术取代针孔技术的动机是基于 以下是事实。针孔的分辨率/灵敏度权衡很好(分辨率和灵敏度都很好 感光度)，但仅在其在图像放大中操作时的小对象(例如，小动物)成像中 模式。在大对象(例如，人)成像中，当针孔以图像缩减模式操作时或当 图像和对象具有相同的大小，分辨率/灵敏度权衡较差(分辨率较差和分辨率较差 敏感度)。此外，在固定系统中，角度视图的数量是有限的，因此，为了获得 视角越多，图像就不能放大。在这种情况下，分段平行孔准直能够 提供比针孔准直更好的分辨率和检测灵敏度。 拟议的研究将仔细研究和比较传统的旋转系统，多个旋转系统和 针孔系统和分段平行孔系统，并将验证我们的假设：对于人类心脏 研究表明，分段平行孔系统的性能将优于多针孔系统和常规 在图像分辨率和检测灵敏度方面的旋转系统。患者可行性研究也在进行中 有计划的。本研究为分段平行孔系统的应用奠定了坚实的基础 常见的临床SPECT相机、患者研究、具有时间一致投影的动态成像，以及 运动矫正技术将在未来的R01拨款下开发。

Segmented-Parallel-Beam Stationary Cardiac SPECT Abstract: The objective of this project is to develop a stationary cardiac SPECT (single photon emission computed tomography) system using a novel segmented parallel-hole collimator mounted on a large-area NaI(Tl) detector. This stationary SPECT system is inexpensive to build, motion-free, and able to acquire consistent SPECT. This system can obtain true dynamic SPECT images. A "stationary" gamma camera for cardiac SPECT has been developed by Spectrum Dynamics, called D- SPECT. There is no gantry rotation in D-SPECT; however, the detectors are continuously sweeping. Therefore, D-SPECT is not a truly stationary system. A genuine stationary cardiac SPECT system has been proposed jointly by UC San Francisco and Western Cardiology Associates. Their system is a modified three-detector SPECT system, mounted with three multi- pinhole collimators. They have successfully acquired cardiac SPECT images using this setup. GE has also developed a stationary, multi-pinhole dedicated cardiac SPECT system called Alcyone. Our proposed research is to replace the multi-pinhole collimators with our original-design segmented parallel-hole collimators. In a segmented parallel-hole collimator, the entire detection area is partitioned into many smaller sub-regions. The collimator holes in each segment point to the heart. Our motivation for replacing the pinhole technology by segmented parallel-hole technology is based on the following facts. The resolution/sensitivity trade-off for the pinhole is excellent (good resolution and good sensitivity), but only in small object (e.g., small animal) imaging when it is operating in the image magnifying mode. In large object (e.g., human) imaging when the pinhole is operating in the image-reducing mode or when image and object have the same size, the resolution/sensitivity trade-off is poor (poor resolution and poor sensitivity). In addition, the number of angular views is limited in a stationary system, thus, in order to obtain more view angles, the images cannot be magnified. In this situation, segmented parallel-hole collimation is able to provide better resolution and detection sensitivity than pinhole collimation. The proposed research will carefully study and compare the conventional rotational systems, the multi- pinhole systems, and segmented parallel-hole systems, and will verify our hypothesis: For human cardiac studies, the segmented parallel-hole system will outperform the multi-pinhole systems and the conventional rotational systems in terms of image resolution and detection sensitivity. Patient feasibility studies are also planned. After this research establishes a solid foundation for the segmented parallel-hole system using a common clinical SPECT camera, patient studies, dynamic imaging with temporally consistent projections, and motion correction techniques will be developed under a future R01 grant.