SUB-MILLIMETER ANIMAL POSITRON EMISSION TOMOGRAPHY (PET)

能够在人类疾病的小动物模型中利用分子成像力量的成像技术--包括正电子发射断层扫描(PET)--是生命科学界的优先事项。在PET中，F-18在组织中发射的正电子范围对小探测器环施加的空间分辨率极限是300-400微摩尔。然而，目前用于动物成像的PET仪器的空间分辨率为1.5-2 mm半高宽。由于511keV光子的穿透性质及其在探测器内的散射倾向，目前的闪烁探测器技术不太可能远远低于这一分辨率并实现足够的性能。这项工作将开发一种替代的探测器技术，可以很容易地利用F-18正电子范围和非线性度所规定的分辨率限制，用于小探测器环直径。与密歇根大学合作进行的第一阶段实验将证明探测器概念的可行性，并为以亚毫米分辨率成像小鼠和大鼠的PET仪器进行初步设计工作。在第二阶段，将最后确定设计，将开发一个模块化、可扩展的探测器系统，并将建造一个包含部分探测器环的原型仪器。第三阶段将基于该技术的动物PET仪器商业化。拟议的商业应用：这项技术的直接应用是在小动物PET领域。目前，商业前景似乎很好，因为调查人员的需求和一家制造商正在创造一个新兴市场。虽然本文提出的工作是为了开发动物PET，但基础技术也有助于改进用于人体的PET--一个诱人的商业前景。

Imaging technologies-including positron emission tomography (PET)- that are capable of exploiting the power of molecular imaging in small animal models of human disease are a priority in the life-sciences community. In PET, the spatial resolution limit imposed by the range of positrons emitted by F- 18 in tissue is 300-400 micromoles for small detector rings. However, current PET instruments for animal imaging have spatial resolutions on the order of 1.5-2 mm FWHM. Due to the penetrating nature of 511 keV photons and their propensity to scatter within the detector, it is unlikely that present scintillation detector technology can be pushed much below this resolution and achieve adequate performance. This work will develop an alternative detector technology that can easily exploit the resolution limits dictated by the F-18 positron range and acolinearity for small detector ring diameters. Phase I experiments conducted in conjunction with the University of Michigan will demonstrate the feasibility of the detector concept and conduct preliminary design work for PET instruments for imaging mice and rats at sub-millimeter resolution. In Phase II, the design will be finalized, a modular, scalable detector system will be developed, and a prototype instrument containing a partial ring of detectors will be constructed. Phase III will commercialize animal PET instruments based on the technology. PROPOSED COMMERCIAL APPLICATIONS: The immediate application of this technology is in the area of small animal PET. At present, commercial prospects appear good since investigator demand and one manufacturer are creating an emerging market. Although the work proposed herein is for development of animal PET, the basic technology lends itself to improving PET for human subjects as well--an attractive commercial prospect.