SIMULTANEOUS DUAL ISOTOPE SPECT W/ CROSS TALK CORRECTION

SPECT的一个独特功能是能够使用两种药物 用不同的同位素标记，发射不同能量的光子 同时测量不同的生理过程。 从两种同位素同时采集投影数据具有 优点是它允许测量两个潜在相关的 过程（例如，静息和应激灌注和受体密度） 同时还研究与讨论这可能会增加额外的诊断信息， 此外，还有实际的优点，如增加病人 吞吐量，消除配准问题， 两项研究中常见的患者运动。 然而，由于分散在 患者和伽马相机以及 传统的伽马相机，双同位素采集将导致 两组投影数据的串扰污染。 在这 我们假设我们可以开发出同时 获取和重建双同位素图像， 这种串扰的影响，以点的图像具有诊断 图像质量接近于采集时的图像质量 分开 我们选择专注于两个特定的应用： 同位素Tc-99 m/T1-201负荷/静息心肌灌注SPECT和双 同位素Tc-99 m/l-123脑SPECT。 为此，我们建议：（1） 开发改进的Tc-99 m/T1-201和Tc-99 m/I-123采集方法 包括最佳能量窗和相对活性的成像：（2） 开发基于迭代重建的补偿方法， 补偿串扰，包括准确的串扰模型- 谈话产生效果：（3）使用体模和 结合图像定量测量的模拟实验 质量，数学观察员和人类观察员研究：和（4） 对同时和单独采集进行临床评价 双同位素静息/负荷心肌灌注成像。 年底 我们相信，在拟议的供资期内， 并评估了可应用于临床的实用方法 静息/负荷心肌灌注SPECT重要应用。 给定 执行此程序的频率和重要性 我们相信，在患者舒适度和临床处理量方面， 这将对临床实践产生重大影响。 我们也将 开发了同时进行Tc-99 m/I-123脑成像的技术 这可能被证明是重要的新的I-123和Tc-99 m标记的脑剂 开发和销售。

One unique feature of SPECT is the ability to use two pharmaceuticals labeled with different isotopes emiting photons with different energies to make simultaneous measurements of different physiological processes. Simultaneous acquisition of projection data from two isotopes has the advantage that it allows measurement of two potentially related processes (e.g., rest and stress perfusion and receptor density) at the same time. This may add additional diagnostic information and, in addition, there are practical advantages such as increased patient throughput, elimination of problems with registration and results in common patient motion in the two studies. However, due to scatter in the patient and gamma camera and the poor energy resolution of conventional gamma cameras, dual isotope acquisition will result in crosstalk contamination of the two sets of projection data. In this work we hypothesize that we can develop methods for simultaneously acquiring and reconstructing dual isotope images that can reduce the effects of this crosstalk to the point where the images have diagnostic image quality close to that which they would have if acquired separately. We have chosen to focus on two specific applications: dual isotope Tc-99m/T1-201 stress/rest myocardial perfusion SPECT and dual isotope Tc-99m/l-123 brain SPECT. Toward this end we propose to: (1) Develop improved acquisition methods for Tc-99m/T1-201 and Tc-99m/I-123 imaging including optimal energy windows and relative activities: (2) develop iterative reconstruction based compensation methods to compensate for the cross-talk including accurate models for the cross- talk producing effects: (3) to evaluate these methods using phantom and simulation experiments combined with quantitative measures of image quality, mathematical observers and human observer studies: and (4) to perform a clinical evaluation of simultaneous and separate acquisition of dual isotope rest/stress myocardial perfusion imaging. At the end of the proposed funding period we believe that we will have developed and evaluated practical methods that can be applied to the clinically important application of rest/stress myocardial perfusion SPECT. Given the frequency with which this procedure is performed and the significant improvement in both patient comfort and clinical throughput, we believe this would have a substantial impact on clinical practice. We also will have developed techniques for simultaneous Tc-99m/I-123 brain imaging that may prove important as new I-123 and Tc-99m labeled brain agents are developed and marketed.