A New High Performance Detector for Small Animal SPECT

描述（由申请人提供）：在各种功能成像技术中，SPECT在小动物疾病模型研究和患者护理中发挥着重要作用。许多spect标记的成像探针具有高度特异性的分布和很少的背景，被用于测量小动物中广泛的重要生物学参数，包括底物代谢、血流量、缺氧、蛋白质合成和受体特性。近年来，随着转基因在体内表达成像方法的发展，这一重要方式的应用得到了显著增强。此外，SPECT具有双同位素成像能力，可以通过单一成像研究将两个生物过程关联起来。最近对小动物SPECT的需求也受到制药行业的推动，制药行业需要对生物过程进行体内量化，以测量药物的作用机制及其在作用部位的浓度。这些应用都需要出色的空间分辨率，不仅因为要成像的细节规模小，而且还因为要求苛刻的检测和估计任务。不幸的是，现有的SPECT仪器不能提供所需的性能，因此开发高分辨率检测器对于改进未来的SPECT系统至关重要。为了解决这些问题，我们建议开发一种基于独特设计的闪烁体耦合到非常高的空间分辨率读出的新型探测器。具体而言，闪烁体的设计和制造将最大限度地减少由于闪烁体内部相互作用深度效应引起的视差误差引起的分辨率损失，同时保持非常高的入射辐射检测效率。闪烁体和读出的这种组合，当耦合到一个定制设计的准直器时，将形成一个SPECT检测器模块，可以实现极好的空间分辨率和高灵敏度，具有成本效益的方式。在探测器模块成功开发之后，后续的工作将集中于开发一个完整的小动物SPECT系统作为原型产品。

DESCRIPTION (provided by applicant): Among the various functional imaging techniques, SPECT maintains an important role in the study of disease models in small animals as well as in patient care. Many SPECT-labeled imaging probes that have highly specific distributions with very little background are being used to measure a wide range of biological parameters of importance in small animals including substrate metabolism, blood flow, hypoxia, protein synthesis and receptor characteristics. The utility of this important modality has been significantly enhanced in recent years by the development of methods to image transgene expression in vivo. Furthermore, SPECT is capable of dual-isotope imaging for correlating two biological processes with a single imaging study. Recent demand for small animal SPECT has also been driven by the pharmaceutical industry where in vivo quantification of biological processes to measure an agent's mechanism of action and its concentration at the site of action is necessary. Each of these applications requires excellent spatial resolution, not only because of the small scale of the details to be imaged but also for the demanding detection and estimation tasks. Unfortunately, existing SPECT instrumentation does not provide the required performance, so the development of a high-resolution detector is essential for the improvement of future SPECT systems. To address these issues, we propose to develop a novel detector based on a unique design of a scintillator coupled to a very high spatial resolution readout. Specifically, the scintillator design and fabrication will minimize the loss of resolution arising from parallax errors due to depth-of-interaction effects within the scintillator, while maintaining very high efficiency for the detection of incident radiation. This combination of scintillator and readout, when coupled to a custom designed collimator, will form a SPECT detector module that can achieve extremely fine spatial resolution and high sensitivity in a cost-effective manner. The effort subsequent to the successful development of the detector module will focus on the development of a complete small-animal SPECT system as a prototype product.