Advanced thin-slab TOF-PET detector module for next generation of brain PET

摘要（30行） 众所周知，美国人寿命的增加导致脑部疾病的患病率增加 和精神疾病，痴呆症和阿尔茨海默氏症对医疗保健系统构成重大挑战。 由于脑正电子发射断层扫描（PET）是一种强大的非侵入性临床研究工具， 研究脑疾病和精神障碍的基本机制，预计将发挥 在应对这一挑战中发挥重要作用。然而，目前的脑PET技术相对受限， 低灵敏度和低空间分辨率，限制了其在这方面的用途。因此，有一个 迫切需要改善脑PET的定量成像性能。为了满足这一需求，我们建议 开发先进的探测器模块和相关算法，特别是利用最近的进展， 飞行时间（TOF）探测器技术。这些单元将为后续项目奠定基础， 开发超高性能专用全脑TOF-PET相机（BRAIN PET EXPLORER）， 研究和临床工作。该设备将克服目前的技术缺陷， 在有效灵敏度和更高的空间分辨率成像方面的实质性增益， 先进的脑部PET系统（NeuroEXPLORER于2022年投入使用）。改善的关键因素 TOF-PET的性能是更好的符合时间分辨率（CTR -到达时间之间的时间差， 两个湮没光子），使得能够将湮没事件精确定位在响应线上。我们 研究是创新的，因为这个概念验证提案的目标是建立和证明这些 新的和先进的薄板TOF-PET探测器模块，并建立其适用于规模扩大，在一个完整的 脑PET探索者（未来的工作）。这些探测器模块将建立CTR <100 ps FWHM性能， 有效灵敏度提高8倍，3D事件定位出色（与当前相比 最先进的扫描仪）。预计有效灵敏度将增加2倍 通过精确确定湮灭光子的第一相互作用点来实现， 探测器块之间的康普顿散射。有效灵敏度的总体> 8倍的增加可用于 降低给予患者的放射性示踪剂的活性，缩短检查持续时间，增加空间 分辨率，或增加动态脑PET成像中的时间分辨率。所有这些因素将使 脑PET是一种更有用、更具成本效益和负担得起的研究和临床工具。这种创新的出现 脑PET技术将有助于解决日益普遍的脑部疾病和精神疾病， 美国人口老龄化。 2

ABSTRACT (30 lines) It is well established that the increasing lifespan in the US is leading to increased prevalence of brain diseases and mental illnesses, with dementia and Alzheimer’s posing significant challenges to the healthcare system. Because brain Positron Emission Tomography (PET) is a powerful noninvasive tool for clinical studies and research on fundamental mechanisms of brain maladies and metal disorders, it is expected to play an important role in addressing this challenge. However, current brain PET technologies are limited with relatively low sensitivity and low spatial resolution, constraining its usefulness in this context. Consequently, there is a critical need to improve quantitative imaging performance of brain PET. To address this need, we propose to develop advanced detector modules and associated algorithms, leveraging in particular recent progress in time-of-flight (TOF) detector technologies. These modules will lay the foundation for a follow-on project to develop an ultra-high-performance dedicated whole-brain TOF-PET camera (BRAIN PET EXPLORER) for research and clinical work. This device will overcome the current technology shortcomings by providing substantial gain in effective sensitivity and much higher spatial resolution imaging over the most current advanced brain PET system (NeuroEXPLORER commissioned in 2022). The crucial factor for improved performance of TOF-PET is better coincidence time resolution (CTR - time difference between arrival of the two annihilation photons) enabling accurate localization of the annihilation event a line-of-response. Our research is innovative because the goal of this proof-of-concept proposal is to build and demonstrate these novel and advanced thin-slab TOF-PET detector modules, and establish their suitability for scale up in a full BRAIN PET EXPLORER (future work). These detector modules will establish CTR <100 ps FWHM performance, enabling an 8× gain in effective sensitivity and outstanding 3D event localization (compared to the current state-of-art scanners) at reduced cost. An additional factor of up to 2× boost in effective sensitivity is expected to be achieved by accurate determination of the point-of-first-interaction for annihilation photons that undergo Compton scatter between detector blocks. The overall > 8× increase in the effective sensitivity can be used to reduce the activity of radiotracer administered to the patient, reduce the examination duration, increase spatial resolution, or increase the temporal resolution in dynamic brain-PET imaging. All these factors will make the brain-PET a more useful, cost-effective and affordable research and clinical tool. The advent of such innovative brain PET technology will help address growing prevalence of brain diseases and mental illnesses facing the aging population of the US. 2