IMPROVED QUANTITATIVE ACCURACY OF SPECT-PET IMAGING

描述(改编自申请者摘要)：最近的商业广告 可添加到符合检测系统上的开发 现有的SPECT摄像机，以及向其提供FDG的药房网络 那些没有现场回旋加速器的医院，已经提供了潜力 对于大量增加的成像研究使用 正电子发射体，如FDG。这项研究提案的目标是 研究提高定量准确度的技术 使用这些新的符合探测系统的FDG-肿瘤学成像。一个 当前伽马相机符合成像系统的主要局限性是 探测器计数速率有限。这项研究计划的一个重要目标是 BE将调查多个不同的数据收集策略 提高了符合率。申请者建议评估和 使用最新开发的制服来优化这些不同的策略 Cramer-Rao(CR)估计符方差的界，它提供了一种度量 可实现的特定估算任务的最佳可能性能 使用测量的投影数据。模拟各种数据收集 策略方面，他们提出修改蒙特卡罗模拟包 (SIMIND)，目前对SPECT成像进行建模，以允许跟踪 湮没光子及其在符合条件下的探测 头部旋转伽马相机。除了调查不同的数据 符合探测系统的收集策略，他们建议 评估不同计算复杂性的重建方法，以及 衰减的补偿程度、探测器响应和 散射可能会影响图像质量。将使用两个品质因数来 客观评估临床相关评估任务的绩效 包括模拟数据和临床数据。要计算这些基于任务的 并评估其准确度和精密度的方法 解析地计算人口统计量，例如平均值， 协方差矩阵，得到图像的概率密度函数 使用非迭代和加速迭代重建方法 将会被开发出来。

DESCRIPTION (Adapted from Applicant's Abstract): The recent commercial development of coincidence detection systems that can be added on to existing SPECT cameras, as well as a pharmacy network to supply FDG to hospitals which do not have a cyclotron on-site, has provided the potential for a vast increase in the number of imaging studies performed using positron emitters such as FDG. The goal of this research proposal is to investigate techniques for improving the quantitative accuracy of FDG-oncological imaging using these new coincidence detection systems. A major limitation of current gamma camera coincidence imaging system is a limited detector count-rate. An important goal of this research plan will be to investigate a number of different data collection strategies for improving the coincidence rate. The applicants proposed to evaluate and optimize these different strategies using the recently developed uniform Cramer-Rao (CR) bound on estimator variance which provides a measure of the best possible performance for a specific estimation task that is achievable using the measured projection data. To simulate various data collection strategies, they proposed to modify a Monte Carlo simulation packaged (SIMIND) which currently models SPECT imaging, to allow for the tracking of annihilation photons and their detection in coincidence using a two or three headed rotating gamma camera. In addition to investigating different data collection strategies for coincidence detection systems, they proposed to evaluate reconstruction approaches of varying computational complexity, and the extent to which compensations for attenuation, detector response and scatter can affect image quality. Two figures of merit will be used to objectively assess performance of clinically relevant estimation tasks using both simulated and clinical data. To compute these task-based figures-of-merit and to evaluate their accuracy and precision, methods to analytically compute population statistical quantities, such as the mean, covariance matrix, and the probability density function of images obtained with both non-iterative and accelerated iterative reconstruction approaches will be developed.