An Anger Approach for 1mm-Resolution Small-Animal PET

描述（由申请人提供）：正电子发射断层扫描（PET）是研究生物体生物功能的强大成像工具。小动物如大鼠和转基因小鼠是研究人类疾病和功能的灵活替代品。因此，小动物PET已成为解决人类健康问题（从成瘾到癌症再到药物开发）的一种快速发展的方法。然而，目前最好的PET技术（~ 2 mm分辨率）在空间分辨率和灵敏度方面仍有很大的局限性，特别是对于小鼠。目前提出的提高分辨率的方法面临着许多技术障碍，这些障碍迫使在性能上进行权衡。 该项目的目标是证明一种新颖的，高性能的，伽马射线探测小动物PET策略的可行性。它本质上是一个小型化和现代化的“愤怒”（或“伽马”）相机，其原理类似于用于单光子发射计算机断层扫描（SPECT）的众所周知的探测器，其中使用连续闪烁体晶体，并且根据光电探测器组之间的光共享来确定位置。与传统设计相比，关键的改进包括更适合PET（LSO）的闪烁体，更薄的晶体以获得更高的分辨率，以及大面积雪崩光电二极管（APD）技术作为光电探测器，允许分层以提高灵敏度，以及其他好处。虽然许多不同的实现是可能的，在这个建议中的目标是开发一个实用的PET探测器，如果在小动物断层扫描仪中使用，实现1毫米半高宽的均匀空间分辨率跨越大部分的视场，灵敏度大于大多数小动物探测器的设计，和一个更具成本效益的结构。拟议的探测器设计的可行性将通过原型建设，性能评估，计算机模拟开发和验证，最后优化的阶段进行彻底的特点。由此产生的优化设计，预计将提供一个无与伦比的组合的小动物PET成像的性能特征。

DESCRIPTION (provided by applicant): Positron emission tomography (PET) is a powerful imaging tool to investigate biological function in living organisms. Small animals such as rats and transgenic mice serve as flexible surrogates for studying human disease and function. Consequently, small-animal PET has become a rapidly growing approach to problems in human health, from addiction to cancer to drug development. However, the best currently available PET technology (~2mm resolution) still has significant limitations in spatial resolution and sensitivity, particularly for the mouse. And currently proposed approaches to improve resolution face a number of technical obstacles which force trade-offs in performance. The goal of this project is to demonstrate the feasibility of a novel, high-performance, gamma-ray detection strategy for small-animal PET. It is essentially a miniaturized and modernized "Anger" (or "gamma") camera, with a principle similar to well-known detectors for single-photon emission computed tomography (SPECT), in which a continuous scintillator crystal is used and position is determined from light-sharing among groups of photodetectors. Critical improvements over the traditional design include a more appropriate scintillator for PET (LSO), a thinner crystal for higher resolution, and large-area avalanche photodiode (APD) technology as the photodetector which allows layering to improve sensitivity, among other benefits. Although many different implementations are possible, the target in this proposal is to develop a practical PET detector which, if used in a small-animal tomograph, achieves a uniform spatial resolution of 1 mm FWHM across most of the field-of-view, sensitivity larger than most small-animal detector designs, and a more cost-effective construction. The feasibility of the proposed detector design will be thoroughly characterized through the phases of prototype construction, performance evaluation, computer simulation development and validation, and finally optimization. The resulting optimized design is expected to provide an unparalleled combination of performance characteristics for small-animal PET imaging.