Enabling Multi-Tracer SPECT Studies of the Human Brain

实现人脑的多示踪剂 SPECT 研究

• 批准号: 9789299
• 负责人: Todd E Peterson
• 金额: $ 42.98万
• 依托单位: VANDERBILT UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-30 至 2022-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9789299
• 关键词: Base of the Brain; Binding; Brain; Brain imaging; Caliber; Cerebrum; Collimator; Consumption; Crystallization; Development; Electrodes; Gamma Cameras; Gamma Rays; Germanium; High temperature of physical object; Human; Image; Imaging technology; Individual; Investigation; Label; Measurement; Measures; Mechanics; Methodology; Modality; Modification; Molecular Probes; Performance; Perfusion; Positron-Emission Tomography; Process; Property; Radioisotopes; Resolution; Sampling; Scanning; Scheme; Sensory Receptors; Signal Transduction; Sodium Iodide; System; Technology; Testing; Time; Tracer; Uncertainty; Work; attenuation; base; computerized data processing; cost; design; detector; experimental study; image processing; imaging approach; imaging capabilities; imaging probe; imaging study; improved; in vivo imaging; minimally invasive; molecular imaging; nonhuman primate; prototype; radiation detector; radiotracer; receptor; simulation; single photon emission computed tomography; technology development; temporal measurement; tool

Project Summary Molecular imaging provides the means to quantitatively study many types of processes in the human brain in a minimally invasive manner. However, the complexity of the brain results in many instances in which it is desirable to be able to study more than one property simultaneously, such as measuring neuroreceptor binding at the same time as transporters or cerebral perfusion together with receptor occupancy. While one option for doing so in some cases may be to use multiple modalities (e.g. PET/MR), if the measurements are to be done with similar sensitivity, spatial resolution, and temporal resolution, then the ability to image multiple probes using a single modality is beneficial. Because SPECT utilizes tracers labeled with radionuclides that emit gamma rays at specific energies, it is often touted for its possibility of imaging multiple radiotracers simultaneously. However, multi-tracer SPECT studies are rarely done in practice due to the limited energy resolution of conventional gamma cameras that necessitates complicated correction schemes to account for crosstalk between the different energy channels. High-purity germanium (HPGe) detector technology provides an order of magnitude improvement in energy resolution over conventional sodium iodide-based gamma cameras, allowing for easy separation of relevant radionuclide photopeaks (e.g. 140 keV for 99mTc and 159 keV for 123I) and the use of narrow energy windows that significantly reduces scatter. We previously have demonstrated the applicability of mechanically-cooled HPGe detectors to SPECT and here propose to pursue further improvements in the technology, including increased crystal size and improved intrinsic spatial resolution. The use of modular cameras facilitates the design of application-specific SPECT systems with good spatial resolution, sensitivity, and angular sampling. We will design a brain-specific SPECT system capable of making simultaneous, quantitative measurements of two or more molecular probes based on the improved HPGe detector technology. In parallel with the detector developments we will demonstrate the multi-tracer methodology through non-human primate SPECT scans that will be acquired using a two-camera prototype system. We will utilize analytical, simulation, and experimental studies in developing a design for a SPECT system for human brain imaging offering unprecedented capabilities for multi-tracer studies.

项目概要 分子成像提供了定量研究人脑中多种类型过程的方法 微创方式。然而，大脑的复杂性导致在许多情况下它是 希望能够同时研究多种特性，例如测量神经受体结合 同时作为转运蛋白或脑灌注以及受体占用。虽然一种选择是 如果要进行测量，在某些情况下可能会使用多种模式（例如 PET/MR） 具有相似的灵敏度、空间分辨率和时间分辨率，则能够对多个探头进行成像 使用单一模式是有益的。因为 SPECT 使用标有放射性核素的示踪剂，这些示踪剂会发射 特定能量的伽马射线，它经常因其对多种放射性示踪剂成像的可能性而受到吹捧 同时地。然而，由于能量有限，多示踪剂 SPECT 研究在实践中很少进行 传统伽玛相机的分辨率需要复杂的校正方案来解决 不同能量通道之间的串扰。高纯锗 (HPGe) 探测器技术提供 与传统的基于碘化钠的伽马射线相比，能量分辨率提高了一个数量级 相机，可以轻松分离相关放射性核素光峰值（例如 99mTc 的 140 keV 和 159 keV for 123I）以及使用窄能量窗可显着减少散射。我们之前有 证明了机械冷却 HPGe 探测器对 SPECT 的适用性，并在此建议追求 该技术的进一步改进，包括增加晶体尺寸和改进固有空间 解决。模块化相机的使用有助于设计特定应用的 SPECT 系统，具有良好的性能 空间分辨率、灵敏度和角度采样。我们将设计一个大脑特异性 SPECT 系统，能够 基于改进的方法对两个或多个分子探针进行同时、定量测量 HPGe探测器技术。在探测器开发的同时，我们将演示多示踪剂 通过非人类灵长类动物 SPECT 扫描的方法，该扫描将使用两个摄像头原型获得 系统。我们将利用分析、模拟和实验研究来开发 SPECT 的设计 人脑成像系统为多示踪剂研究提供前所未有的功能。