Comprehensive Validation of Cardiac SPECT Reconstruction

描述（由申请人提供）：诊断和定量准确性 心脏SPECT的成像受到深度依赖性模糊、衰减、散射 和图像噪声。纠正这些物理效应的方法已经被 描述，但没有广泛用于临床，主要是由于缺乏 全面验证。我们建议集中领导才能 核心脏病学的研究人员来验证最有前途的技术， 具体如下：目标1。利用OSEM的严格实施，包括 衰减、准直器模糊和位移变化散射的模型（Tsui和 同事），用我们自己的方法，这是不那么严格，但产生了 优秀的人类多中心试验结果，作为比较的基线。目的 2.为了评估这些方法的定量准确性， 计算机模拟和实际幻影：MCAT和NCAT代码，以产生一个 一系列不同“缺陷”的模拟（就位置、大小和 “局部缺血”程度），具有不同程度的衰减、散射和模糊， 以及最新的数据频谱心脏模型，它能够“跳动”。" 物体中的“真实”放射性浓度（即，模型之前， 模拟）或体模将用作比较的基线。目标3：到 在一系列狗研究中评估这些方法的定量准确性 通过可变冠状动脉的实验性诱导缺血模型 闭塞，具有不同的缺血区域（就位置和严重程度而言）。 心肌灌注的真实分布，通过微球测量 离体计数，将作为比较的基线。目标4。评估 这些方法对视觉诊断准确性的影响 人体多中心临床试验解释和极图量化 SPECT在冠状动脉疾病诊断中的应用。的结果 冠状动脉血管造影将作为比较的基线。假设：The OSEM方法将具有显著更好的诊断和定量 准确性优于其他方法，在临床上重要的幅度，特别是 在轻症患者中。

DESCRIPTION (Provided by Applicant): The diagnostic and quantitative accuracy of cardiac SPECT are limited by depth-dependent blurring, attenuation, scatter, and image noise. Approaches to correct for these physical effects have been described, but are not widely used clinically, primarily due to lack of comprehensive validation. We propose to pooi the talents of leading investigators in nuclear cardiology to validate the most promising techniques, as follows: Aim 1. To utilize a rigorous implementation of OSEM that includes models of attenuation, collimator blur, and shift-variant scatter (Tsui and colleagues), with our own approach, which is less rigorous but has produced excellent human multi-center trial results, as a baseline for comparison. Aim 2. To assess the quantitative accuracy of these approaches in a series of computer simulations and actual phantoms: the MCAT and NCAT code to produce a series of simulations of different "defects" (in terms of location, size, and degree of "ischemia"), with varying degrees of attenuation, scatter, and blur, and the newest Data Spectrum cardiac phantom, which is capable of "beating." The "true" activity concentration in the object (i.e., the model prior to simulation) or phantom will serve as the baseline for comparison. Aim 3. To assess the quantitative accuracy of these approaches in a series of dog studies with a model of experimentally-induced ischemia via variable coronary artery occlusion, with different ischemic regions (in terms of location and severity). The true distribution of myocardial perfusion, as measured by microspheres counted ex vivo, will serve as the baseline for comparison. Aim 4. To assess the effects of these approaches on the diagnostic accuracy of visual interpretation and polar-plot quantification of human multi-center clinical SPECT studies in the diagnosis of coronary artery disease. The results of coronary angiography will serve as the baseline for comparison. Hypotheses: The OSEM approach will have significantly better diagnostic and quantitative accuracy than other approaches, clinically important in magnitude, especially in mild disease patients.