IN VIVO RADIONUCLIDE QUANTITATION USING EMISSION CT

该项目的长期目标是提高临床实用性 单光子发射计算机断层扫描（SPECT）在体内成像 Tc-99 m-放射性标记的药物分布，并改善SPECT 重要的生物分布参数的量化，如 活动、浓度和体积。具体来说，一个临床 这项研究的重点涉及检测和表征 静脉注射后心肌灌注减少的区域 给药Tc-99 m标记的司他米比。 第二次临床 本申请涉及研究改进的方法， 放射治疗计划这些任务的重点涉及使用 定量SPECT肺灌注成像，以评估 正常肺组织进行放射治疗。主要的假设是 该项目是，它是有可能开发统一的SPECT采集和 用于改善所有区域的临床成像的重建策略 胸（即肺和心脏）。我们建议 通过i）制定和实施适当的假设来调查假设 不对称扇形束传输数据采集几何结构， 准确地确定线性衰减系数的图; ii） 开发和实施组合扇束/平行束， 束/锥形束发射数据采集几何结构; iii）开发和 实施SPECT重建策略， 非均匀衰减、散射和系统几何形状的影响 胸部所有区域的反应，并且临床上 可接受的重建时间。 使用呼吸和/或 心电图门控数据采集，结合统计学 的形态变换将进行研究，以减少 由呼吸和心脏引起的运动模糊的退化效应 收缩运动，并提高准确性和减少偏见，在 重建图像这种统一的战略提供了潜力， 改善对减少的区域的检测和定性 心肌灌注此外，改进活动的量化， SPECT肺灌注图像中的浓度将导致新的 评估肺组织对辐射的反应的方法，其可用于 开发改进的肺癌放射治疗方法。的 新开发的SPECT采集和重建方法将是 通过Monte Carlo模拟进行评估，实验获得 体模数据，并与试点患者研究。受试者工作 特征研究将用于评估新的SPECT成像 心肌灌注缺损检测策略。

The long term goals of this project are to enhance the clinical utility of single photon emission computer tomography (SPECT) to image in vivo Tc-99m-radiolabeled pharmaceutical distributions, and to improve SPECT quantification of important biodistribution parameters such as activities, concentrations, and volumes. Specifically, one clinical focus of this research involves the detection and characterization of regions of decreased myocardial perfusion following intravenous administration of Tc-99m-labeled sestamibi. A second clinical application relates to the investigation of improved approaches for radiation treatment planning. The focus of this tasks involves the use of quantitative SPECT lung perfusion imaging to assess the response of normal lung tissue to radiation treatment. The main hypothesis of this project is that it is possible to develop unified SPECT acquisition and reconstruction strategies for improved clinical imaging in all regions of the chest (that is, the lungs as well as the hear). We propose to investigate the hypothesis by i) developing and implementing appropriate asymmetric fan beam transmission data acquisition geometries to accurately determine maps of the linear attenuation coefficients; ii) developing and implementing combined fan beam/parallel beam, and fan beam/cone beam emission data acquisition geometries; iii) developing and implementing SPECT reconstruction strategies that accurately account for the effects of non-uniform attenuation, scatter and system geometric response for all regions of the thorax, and that have clinically acceptable reconstruction times. The use of the respiratory and/or electrocardiogram gated data acquisition, coupled with statistically based morphometric transformations will be investigated to reduce the degrading effects of motion blurring caused by respiratory and cardiac contractile motions, and to improve accuracy and reduce bias in the reconstructed image. This unified strategy offers the potential to improve the detection and characterization of areas of decreased myocardial perfusion. Also, the improved quantification of activities and concentrations in SPECT lung perfusion images will result in a new method to assess lung tissue response to radiation that may be used to develop improved approaches for radiation treatment of lung cancer. The newly developed SPECT acquisition and reconstruction methodology will be evaluated with Monte Carlo simulations, with experimentally acquired phantom data, and with pilot patient studies. Receiver operating characteristic studies will be used to evaluate the new SPECT imaging strategy for detection of myocardial perfusion defects.