Development of a Low Cost High Performance Animal PET

描述（由申请人提供）：该项目的长期目标是通过（a）提高成像分辨率、图像质量、灵敏度和功能，以及（B）大幅降低动物PET的成本，使更多的生物实验室能够负担得起这种有用的分子成像技术，来加速癌症、药物开发、基因表达和治疗领域的研究和发现。动物模型，如基因工程小鼠，已被证明是这些领域的首选工具。当生物化学和制药过程在体内用PET成像和研究时，这些工具具有更大的价值。然而，具有高分辨率的啮齿动物PET太贵了，大多数生物学家都负担不起（550，000 - 750，000美元）。其次，成像分辨率应进一步提高，以探测小鼠体内更小的结构，检测更小的病变和监测更小的肿瘤。第三，从一开始，动物PET的发展就一直只关注分辨率，而牺牲了检测灵敏度和成本。灵敏度的妥协主要是由于其技术的高成本，通过降低轴向视场（AFOV）使用较少的探测器。然而，随着分辨率的提高（更小的探测器像素，但更多的像素），对更多计数（灵敏度）的需求变得更加迫切，以便保持每个探测器像素的相同统计质量。因此，除非也提高检测灵敏度，否则不能实现更高分辨率的全部益处。此外，灵敏度可用于探测较低水平的生化活性并提高通量。我们建议以一半的成本开发动物PET，同时提供比当前商业系统更高的分辨率，加上2.6-7倍的灵敏度。它还具有55%更大的AFOV，以增加吞吐量，并以更均匀的图像质量在一个床位置对整个转基因小鼠进行成像，并有助于及时成像全身动态变化。大AFOV和高分辨率允许对动脉输入功能进行成像，以量化示踪剂动力学。这种高性能低成本系统基于我们的低成本PET探测器设计、新型高效探测器生产工程技术和电子技术。该系统还使我们能够研究一种新的3-D数据采集和重建方法，从而可以采集所有4 π立体角的发射线（“完整的3-D数据”）。该方法可以进一步改善图像质量和三维图像重建过程。

DESCRIPTION (provided by applicant): The long-term objective of the project is to accelerate research and discoveries in the areas of cancer, drug development, gene expression and therapy by (a) improving the imaging resolution, image quality, sensitivity and functionality, and (b) substantially lowering the cost of animal PET so more biology laboratories can afford this useful molecular imaging technology. Animal models, such as genetically engineered mice, have proven to be the tools of choice in these areas. These tools have even greater value when the biochemical and pharmaceutical processes are imaged and studied in vivo with PET. However, a rodent-PET with high resolution is too expensive to be within the reach of most biologists ($550,000-$750,000). Secondly, the imaging resolution should be improved further to probe smaller structures in mice, to detect smaller lesions and monitor smaller tumors. Thirdly, since inception, animal PET development has always been focusing solely on resolution at the expenses of detection sensitivity and cost. The compromise in sensitivity is mainly due to the high cost of its technology by resorting to decreasing the axial field of view (AFOV) to use fewer detectors. However, as resolution improves (smaller detector pixels but more pixels), the need for more counts (sensitivity) becomes more acute so as to maintain the same statistical quality per detector pixel. Hence, unless detection sensitivity is also improved, the full benefit of higher resolution cannot be realized. Furthermore, sensitivity is useful for probing lower levels of biochemical activities and to improve throughput. We propose to develop an animal PET at half the cost, while providing higher resolution than current commercial system, plus a 2.6-7 times higher sensitivity. It also has a 55% larger AFOV to increase throughput and to image the whole transgenic mouse in one bed position with more uniform image quality and to facilitate imaging wholebody dynamic changes in time. The large AFOV and ultrahigh resolution allow arterial input function to be imaged for quantifying tracer dynamics. This high performance low cost system is based on our low-cost PET detector design, novel efficient detector-production engineering technology, and electronic technology. The system also enable us to the study of a new 3-D data-acquisition and reconstruction method, whereby emission lines from all 4-pi-solid-angles can be acquired ("complete 3-D data"). This method may further improve image quality and the 3-D image reconstruction process.