A Trapezoidal, Slat Crystal PET Detector for Multimodality PET Imaging

描述（由申请人提供）：本提案的主要目标是开发一种具有相互作用深度（DOI）定位的高分辨率、高检测效率正电子发射断层扫描（PET）检测器，其还将支持多模态成像（例如，PET/MR）。这种探测器的设计可以扩展到支持从小鼠到人的成像应用。这种PET探测器的关键设计特点是使用梯形盐晶体（TSC）和最大似然定位方法，我们称之为基于统计的定位（SBP）。除了独特的晶体几何形状外，该设计还将利用硅光电倍增管（SiPM）阵列。SiPM是盖革模式雪崩光电二极管器件，对于PET探测器，特别是对于PET-MR应用，具有非常有吸引力的性能特性。在这个R21提案中，我们将研究为小动物PET成像量身定制的设计。该设计将支持<0.8 mm image resolution and >15%的绝对检测效率。可以设想，根据该提议开发的探测器最终将用于制造非常紧凑的PET探测器环，其将与高场（例如，&gt;4.7T）MR系统。对于该原型工作，TSC PET探测器尺寸将针对约6.0 cm的系统内环直径进行设计。该直径将支持专用PET和PET/MR全身小鼠和大鼠脑成像。这项工作的最终结果是开发和评估一种新的PET探测器设计，该设计将提供最先进的成像性能能力，并且可以用作紧凑的独立PET系统的一部分或用作多模态成像系统的一部分（例如，PET/MR）。我们相信，这种设计将提供一个出色的性能和成本之间的平衡，该设计将转化为商业适应。该建议建立在研究人员开发高分辨率分立晶体PET探测器和高分辨率单片晶体PET探测器的先前工作的基础上。这种新的设计协同结合了两种方法的固有优势，即模块化和出色的空间分辨率控制（分立晶体）以及更低的制造成本 和使用单侧读出（连续晶体）的固有DOI定位能力。该设计可扩展以支持超高分辨率小动物成像;高分辨率器官特异性成像;和全身PET成像。此外，该项目还将增加有关如何优化SiPM设备在核医学成像探测器应用中的使用的知识。两个具体领域，这项工作将有助于开发SiPM信号复用技术，以优化性能与成本，并开发温度控制策略和温度/增益相关的校准程序的SiPM设备。 公共卫生相关性：该提案的总体目标是开发将用于推进PET和多模态PET成像的生物应用的技术。PET是用于临床和研究应用两者的非常重要的成像模态（例如，肿瘤学、心脏病学、神经病学、药物开发、生物分布研究、细胞运输等）。当其与高分辨率解剖成像模态（例如，PET/CT或PET/MR）。任何PET系统的关键组件都是探测器设计。在该提案中，我们介绍了一种新的梯形，板条晶体（TSC）PET探测器，可扩展之间的小动物成像和人体全身成像。我们相信该设计将提供最先进的成像性能和经济的价格点，使得该设计将可转化为商业生产。因此，虽然本提案的重点是特定的PET探测器设计，但本工作的深远目标 是开发PET成像技术，这将有助于对抗人类疾病。

DESCRIPTION (provided by applicant): The principle objective of this proposal is to develop a high resolution, high detection efficiency positron emission tomography (PET) detector with depth-of-interaction (DOI) positioning that will also support multi-modality imaging (e.g., PET/MR). This detector design can be scaled to support imaging applications from mice to man. The key design features of this PET detector are the use of trapezoidal, salt crystals (TSC) and a maximum likelihood positioning method that we call statistics based positioning (SBP). In addition to the unique crystal geometry, the design will utilize silicon photomultiplier (SiPM) arrays. SiPMs are Geiger-mode avalanche photodiode devices that have very attractive performance characteristics for PET detectors, especially for PET-MR applications. In this R21 proposal, we will investigate a design tailored for small animal PET imaging. The design will support <0.8 mm image resolution and >15% absolute detection efficiency. It is envisioned that the detectors developed under this proposal will eventually be used to fabricate a very compact PET detector ring that will be compatible with operation in high field (e.g., >4.7T) MR systems. For this prototype work the TSC PET detector dimensions will be designed for a system inner ring diameter of ~6.0 cm. This diameter will support dedicated PET and PET/MR whole body mouse and rat brain imaging. The net result of this work is the development and evaluation of a new PET detector design that will provide state of the art imaging performance capabilities and that can be used as part of a compact, stand alone PET system or as part of a multi-modality imaging system (e.g., PET/MR). We believe that this design will provide an outstanding balance between performance and cost and that the design will be translatable to commercial adaptation. This proposal builds upon the previous work of the investigators developing high resolution discrete crystal PET detectors and high resolution monolithic crystal PET detectors. This new design synergistically brings together the inherent strengths of both methods, that is, modularity and excellent spatial resolution control (discrete crystals) and lower fabrication costs and inherent DOI positioning capability using single-sided readout (continuous crystals). The design is scalable to support ultra-high resolution small animal imaging; high resolution organ specific imaging; and whole-body PET imaging. In addition, this project will add to the knowledge based on how to optimize the use of SiPM devices for nuclear medicine imaging detector applications. Two specific areas in which this work will contribute are developing SiPM signal multiplexing techniques to optimize performance versus cost and developing temperature control strategies and temperature/gain dependent calibration procedures for SiPM devices. PUBLIC HEALTH RELEVANCE: The overall goal of this proposal is to develop technology that will be used to advance the biological applications of PET and multi-modality PET imaging. PET is a very important imaging modality for both clinical and research applications (e.g., oncology, cardiology, neurology, drug development, biodistribution studies, cell trafficking, etc.). Further great synergism has been demonstrated when it is combined with a high resolution anatomic imaging modality (e.g., PET/CT or PET/MR). The key component of any PET system is the detector design. In this proposal, we introduce a new trapezoidal, slat crystal (TSC) PET detector that is scalable between small animal imaging and human whole body imaging. We believe that this design will provide state of the art imaging performance and an economical price point such that the design will be translatable to commercial production. Therefore while the focus of this proposal is on a specific PET detector design, the far reaching goal of this work is to develop PET imaging technology that will aid in the battle against human disease.