Exploring the Benefits of Time-of-Flight PET

探索飞行时间 PET 的优势

• 批准号: 7314344
• 负责人: WILLIAM W MOSES
• 金额: $ 75.63万
• 依托单位: UNIVERSITY OF CALIF-LAWRENC BERKELEY LAB
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-15 至 2011-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7314344
• 关键词: Algorithms; Caliber; Clinical; Data; Depth; Detection; Development; Dimensions; Dose; Electronics; Facility Construction Funding Category; Future; Goals; Image; Imaging Techniques; Individual; Measurement; Measures; Medical; Medical Technology; Methods; Modeling; Neurology; Noise; Ocular orbit; Patients; Performance; Positron; Positron-Emission Tomography; Purpose; Research Personnel; Resolution; Source; Staging; System; Technology; Time; Today; Tube; attenuation; base; clinically relevant; concept; detector; human subject; improved; infancy; interest; novel; oncology; photomultiplier; programs; prototype; reconstruction; simulation; size; theories; time use; tumor; whole body imaging

DESCRIPTION (provided by applicant): Simple theory predicts that the imaging time or injected dose in a PET study can be reduced by roughly an order of magnitude by using time-of-flight (TOP) information. This reduction can be obtained by improving the coincidence timing resolution, and so would be achievable in clinical, whole body studies using with PET systems that differ little from existing cameras. The purpose of this proposal is to realize the best possible timing resolution in a prototype PET camera and verify the performance improvement experimentally, measuring how the improvement depends on the timing resolution. The potential impact of this development is large, especially for oncology studies in large patients, where it is sorely needed. Time-of-flight PET was extensively studied in the 1980's but died in the 1990's, as it was impossible to reliably achieve sufficiently good timing resolution without sacrificing other PET performance aspects. Recent improvements in technology have renewed interest in TOP PET, but changes in the last decade in both technology and the medical uses for PET mean that the true benefits of TOP in modern clinical PET are not well understood. By quantifying these benefits as a function of timing resolution, we will guide future commercial and academic TOP PET camera designers by allowing them to make informed choices. To realize this goal, we will construct a single ring "demonstration" PET camera with LSO scintillator crystals that achieves 300 ps coincidence timing resolution. This is a factor of two better timing resolution than any LSO-based PET camera ever constructed or currently proposed, and the simple estimates predict that it would reduce the noise variance by a factor of 8 in whole body imaging. Clinically, this variance reduction could reduce image noise, decrease the injected dose, shorten the imaging time, or provide a combination of these benefits. We will quantify the improvement in noise as a function of timing resolution using a combination of simulation, phantom, and human subject studies, including the clinically relevant tasks of tumor detection and staging. We will then rebuild the camera with a newly developed scintillator (Lul3:Ce) that has exceptional PET performance (high sensitivity, 3% energy resolution, and 125 ps timing resolution) and repeat these measurements. This timing resolution is over three times better than any TOP camera ever built or proposed, and is predicted to give an enormous (18-fold) noise variance reduction.

描述（由申请人提供）：简单的理论预测，通过使用飞行时间（TOP）信息，PET 研究中的成像时间或注射剂量可以减少大约一个数量级。这种减少可以通过提高重合定时分辨率来实现，因此可以在使用与现有相机几乎没有区别的 PET 系统的临床全身研究中实现。该提案的目的是在原型 PET 相机中实现最佳的定时分辨率，并通过实验验证性能改进，测量改进如何依赖于定时分辨率。这一发展的潜在影响是巨大的，尤其是对于大患者的肿瘤学研究，这是迫切需要的。飞行时间 PET 在 1980 年代得到广泛研究，但在 1990 年代消亡，因为在不牺牲其他 PET 性能方面的情况下不可能可靠地实现足够好的定时分辨率。最近技术的进步重新燃起了人们对 TOP PET 的兴趣，但过去十年中 PET 技术和医疗用途的变化意味着 TOP 在现代临床 PET 中的真正好处尚未得到充分了解。通过将这些优势量化为时间分辨率的函数，我们将指导未来的商业和学术 TOP PET 相机设计师，让他们做出明智的选择。为了实现这一目标，我们将构建一个带有 LSO 闪烁体晶体的单环“演示”PET 相机，可实现 300 ps 重合定时分辨率。这比曾经建造或目前提出的任何基于 LSO 的 PET 相机的定时分辨率要好两倍，并且简单的估计预测它将在全身成像中将噪声方差降低 8 倍。在临床上，这种方差的减少可以减少图像噪声、减少注射剂量、缩短成像时间或提供这些好处的组合。我们将结合模拟、模型和人体研究，包括肿瘤检测和分期的临床相关任务，将噪声的改善量化为时间分辨率的函数。然后，我们将使用新开发的闪烁体 (Lul3:Ce) 重建相机，该闪烁体具有出色的 PET 性能（高灵敏度、3% 能量分辨率和 125 ps 定时分辨率），并重复这些测量。这种定时分辨率比任何曾经建造或提出的 TOP 相机都要好三倍以上，并且预计将带来巨大（18 倍）的噪声方差降低。