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.

项目摘要 分子成像提供了定量研究人脑中多种类型过程的手段 微创方式。但是，大脑的复杂性导致了许多实例 希望能够同时研究多个特性，例如测量神经受体结合 与转运蛋白或脑灌注以及受体占用同时。而一个选项 在某些情况下，这样做可能是使用多种方式（例如PET/MR），如果要进行测量 具有相似的灵敏度，空间分辨率和时间分辨率，然后具有成像多个探针的能力 使用单一模态是有益的。因为SPECT利用了用放射性核素标记的示踪剂 伽玛射线处于特定能量，通常因成像多个放射性示例的可能性而被吹捧 同时地。但是，由于能量有限，很少在实践中进行多跟踪SPECT研究 常规伽马相机的解决方案需要复杂的校正方案来考虑 不同能量通道之间的串扰。高纯度锗（HPGE）检测器技术提供 基于碘化钠的伽玛的能量分辨率的数量级改善了 摄像机，允许轻松分离相关的放射性核素照相座（例如，140 keV，99mtc和159 kev用于123i），并使用狭窄的能量窗口可显着减少散射。我们以前有 证明了机械冷却的HPGE探测器的适用性，并在此提议追求 该技术的进一步改进，包括增加晶体尺寸和固有空间的改善 解决。模块化摄像机的使用有助于使用良好的应用特定SPECT系统的设计 空间分辨率，灵敏度和角采样。我们将设计一个能够的大脑特异性SPECT系统 基于改进的两个或多个分子探针同时进行定量测量 HPGE检测器技术。与探测器的开发并行，我们将演示多通道 通过非人类灵长类动物Spect扫描方法将使用两个摄像机原型获取 系统。我们将利用分析，模拟和实验研究来开发SPECT的设计 人脑成像系统为多追踪研究提供前所未有的功能。