RSH SPECT--A ROTATING SLANT HOLE SPECT SCANNER

RSH SPECT--旋转斜孔光谱扫描仪

• 批准号: 6043884
• 负责人: ROLF CLACKDOYLE
• 金额: $ 10.27万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-08-01 至 2000-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6043884
• 关键词: bioimaging /biomedical imaging; biomedical equipment development; brain imaging /visualization /scanning; cardiography; phantom model; single photon emission computed tomography

Single photon-emission computed tomography (SPECT) is a well-established procedure in diagnostic nuclear medicine used for a variety of studies, of which cardiac and brain imaging are the most important. The nuclear medicine used for a variety of studies, of which cardiac and brain imaging are the most important. The tomographic image quality, which ultimately determines the diagnostic utility of SPECT, depends mainly on the number of photons that can be collected during a patient scan. This proposal describes an inexpensive, novel adaptation of SPECT that will provide at two to four times the photon sensitivity, thereby allowing significantly improved detection of lesions or increased patient throughput due to shorter scan times. The conventional parallel-hole collimator is replaced by a rotating slant- hole (RSH) collimator whose multiple segments simultaneously gather two or more projection views of the organ of interest. This increased photon sensitivity comes at the cost of a reduced active imaging region (the "common volume" or CV in the proposal), so the approach is useful only for imaging smaller organs such as the heart and brain. Converging collimators, such as fan-beam, cone-beam, and variable focal-length collimators, apply athe same principle of reducing the CV to gain sensitivity, but rarely achieve even a factor of two increase in sensitivity, and most of them introduce image reconstruction difficulties and require extended scanning motions for a tomographically complete dataset. The RSH SPECT geometry requires no extra scanning motions and uses straightforward three-dimensional (3D) image reconstruction techniques. The goal of this project is to build and evaluate a prototype RSH SPECT scanner. The primary objective is to demonstrate increased photon sensitivity. Other major issues are; susceptibility to background activity: correction procedures for photon attenuation; and patient positioning with a limited imaging volume. The unique combination of collimator rotation with detector gantry motion introduces some unexpected and interesting features. The fully 3D geometry introduces new challenges for attenuation correction methods. An unusual sensitive region (SV) to background radioactivity suggests an attractive new scanning configuration for brain imaging, but might introduce artifacts in heart imaging if there is strong uptake in nearby organs. The research program consists of 5 stages. Stage I involves collimator design and software development. Stage II consists of initial evaluations of the prototype scanner using phantoms. Stage II addresses the problem of attenuation correction for this unusual tomographic geometry; several approaches will be implemented and evaluated. In stage IV, state-of-the- art corrections for Compton scattered background and geometric collimator response will be implemented. In stage V a set of phantom experiments will be used to evaluate and characterize the RSH SPECT system. The main experimental tools, computer stimulations and phantoms, will be developed at the beginning of the project.

单光子发射计算机断层扫描 (SPECT) 是一种成熟的 用于各种研究的诊断核医学程序 其中心脏和大脑成像最为重要。 核 用于各种研究的医学，其中心脏和大脑成像 是最重要的。 最终的断层扫描图像质量 决定SPECT的诊断效用，主要取决于SPECT的数量 可以在患者扫描期间收集的光子。 这个提议 描述了 SPECT 的一种廉价、新颖的改编，它将提供 光子灵敏度的两到四倍，从而允许显着 改善病变检测或增加患者吞吐量 更短的扫描时间。 传统的平行孔准直器被旋转倾斜准直器取代 孔（RSH）准直器，其多个段同时收集两个或 更多感兴趣器官的投影视图。 这增加了光子 灵敏度是以减少活动成像区域为代价的（ “共同卷”或提案中的简历），因此该方法仅适用于 对心脏和大脑等较小的器官进行成像。 汇聚 准直器，例如扇束、锥束和可变焦距 准直器，应用减少 CV 增益的相同原理 灵敏度，但很少能实现甚至两倍的提高 敏感性，并且大多数都会带来图像重建的困难 并且需要延长扫描动作才能获得完整的断层扫描 数据集。 RSH SPECT 几何结构不需要额外的扫描运动 使用简单的三维 (3D) 图像重建 技术。 该项目的目标是构建和评估原型 RSH SPECT 扫描器。 主要目标是证明光子增加 敏感性。 其他主要问题是； 对背景的敏感性 活动：光子衰减的校正程序；和病人 在有限的成像体积下进行定位。 准直器旋转与探测器机架运动的独特组合 引入了一些意想不到的有趣的功能。 全 3D 几何 给衰减校正方法带来了新的挑战。 一个不寻常的 对背景放射性的敏感区（SV）表明一个有吸引力的 用于脑成像的新扫描配置，但可能会引入伪影 在心脏成像中，如果附近器官有强烈的吸收。 研究计划分为5个阶段。 第一阶段涉及准直器 设计和软件开发。 第二阶段包括初步评估 使用模型的原型扫描仪。 第二阶段解决的问题 针对这种不寻常的断层摄影几何形状的衰减校正；一些 将实施和评估方法。 在第四阶段，最先进的 康普顿散射背景和几何准直器的艺术校正 将实施响应。 在第五阶段，一组幻影实验将 用于评估和表征 RSH SPECT 系统。 主要 将开发实验工具、计算机刺激和模型 在项目开始时。