PET-EPRI

基本信息

批准号：
9759919
负责人：
RAYMOND ROBERT RAYLMAN
金额：
$ 59.33万
依托单位：
WEST VIRGINIA UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-08 至 2022-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9759919
关键词：
Anatomy Animals Area Biochemistry Biological Biomedical Research Cell Proliferation Characteristics Chemicals Complex Computer software Computers Cone Coupled Detection Development Diagnosis Electromagnetics Electron Spin Resonance Spectroscopy Elements Event Functional Imaging Glycolysis Goals Heart Neoplasms Human Hybrids Hyperplasia Hypoxia Image Image Enhancement Imaging technology Incidence Individual Interruption Investigation Knowledge Lead Light Magnetic Resonance Imaging Magnetism Malignant Neoplasms Maps Measurement Metabolism Metastatic breast cancer Metastatic to Methods Modality Molecular Probes Mouse Mammary Tumor Virus Mus Neoplasms Normal tissue morphology Photons Physiological Physiology Positioning Attribute Positron-Emission Tomography Process Protocols documentation Research Research Personnel Resolution Scanning Shapes Silicon Solid Standardization Structure Surface System Systems Development Systems Integration Technology Testing Time Tissues Transgenic Mice Translating Tumor Markers Tumor Tissue X-Ray Computed Tomography anatomic imaging animal imaging base carcinogenesis carcinogenicity clinical practice design design and construction detector disorder prevention experience extracellular fluorodeoxyglucose positron emission tomography image registration imager imaging modality imaging potential imaging probe imaging system in vivo insight magnetic dipole magnetic field malignant breast neoplasm novel operation photomultiplier portability pre-clinical seal software development tool tumor tumor microenvironment

项目摘要

The advent of hybrid scanners, combining complementary modalities, has revolutionized imaging; enhancing clinical practice and biomedical research. The standard paradigm is to combine an anatomical imaging method (X-ray CT, for example) with a functional method (PET, for example). In this project we propose a shift of this paradigm by investigating the melding of two complementary, functional imaging methods. Specifically, we plan to integrate a PET scanner with an electron paramagnetic resonance imaging (EPRI) scanner. EPRI is a relatively new method, capable of mapping the in vivo chemical characteristics of tissue. A combined PET- EPRI scanner has the promise to provide new insights into physiologic interactions in microenvironments not currently attainable with current imagers. Development of the PET/EPRI system is technically challenging, requiring unique approaches to scanner design, construction and testing. We will utilize a novel PET scanner that replaces a ring of discrete detector modules with a solid annulus of scintillator (spatial resolution= ~1mm). This design eliminates conductive material needed to construct discrete detector modules. Use of annular scintillator results in high detection sensitivity (~10%) due to elimination of gaps between discrete modules. It also permits estimation of event depth-of-interactions in the detector by correlating light cone shape with depth, a capability not possible with discrete detectors. Arrays of silicon photomultipliers (SiPM), which are not affected by the presence of magnetic fields present in EPR systems, will be used to detect scintillator light. The EPRI system will utilize the rapid scanning method to produce spatial maps of spectra obtained from molecular probes (resolution <1mm). We plan to use a nested design in which the animal handling enclosure, where the system’s RF resonator, shielding, EPR scan coils, PET scanner and gradient coils are combined into a single, compact PET-EPRI insert. The insert will be mounted on a computer-controlled gantry, permitting positioning inside the electro-dipole magnet (400G) required for EPR. The portable animal enclosure will include a grid of fiducial markers to facilitate registration with images acquired on our group’s small animal, MRI scanner. Initial testing of the PET/EPRI scanner will be performed using standardized testing protocols and phantoms emulating physiologic microenvironments. To demonstrate the potential utility of the new system, it will be used in a study of the interaction between the intra-and extracellular components of tumor microenvironments. This investigation will utilize MMTV-PyMT-transgenic mice that spontaneously-develop breast cancer. 18F-fluorodeoxyglucose (FDG)-PET imaging will be used to quantify areas of enhanced glycolysis (intracellular component), while EPR imaging, using a multifunctional trityl probe, will be used to quantify hypoxic and acidic areas (extracellular component) at extended time points as hyperplasia evolves in to metastatic breast cancer. The resulting information will help explore the hypothesis that carcinogenic progression is an evolutionary process, and illustrate the unique capabilities of a combined PET-EPRI scanner.

混合扫描仪的出现结合了互补模式，彻底改变了成像增强技术。临床实践和生物医学研究的标准范式是将解剖成像方法结合起来。（例如 X 射线 CT）与功能方法（例如 PET）在这个项目中我们提出了这种转变。具体来说，我们通过研究两种互补的功能成像方法的融合来研究范例。计划将 PET 扫描仪与电子顺磁共振成像 (EPRI) 扫描仪集成。一种相对较新的方法，能够绘制组织体内化学特征的组合 PET-。 EPRI 扫描仪有望为微环境中的生理相互作用提供新的见解目前，PET/EPRI 系统的开发在技术上具有挑战性，需要独特的扫描仪设计、构建和测试方法，我们将使用新型 PET 扫描仪。它用闪烁体的实心环取代了离散探测器模块环（空间分辨率=〜1毫米）。该设计消除了构建分立探测器模块所需的导电材料。由于消除了分立模块之间的间隙，闪烁体具有高检测灵敏度（~10%）。还允许通过将光锥形状与深度相关联来估计探测器中的事件交互深度，分立式探测器 (SiPM) 无法实现这一功能。受 EPR 系统中存在的磁场的影响，将用于检测闪烁体光。 EPRI 系统将利用快速扫描方法生成从以下位置获得的光谱空间图：我们计划使用嵌套设计，其中动物处理外壳，系统的射频谐振器、屏蔽、EPR 扫描线圈、PET 扫描仪和梯度线圈组合在一起插入一个紧凑的 PET-EPRI 插入件，该插入件将安装在计算机控制的龙门架上。放置在 EPR 所需的电偶极磁铁 (400G) 内。包括基准标记网格，以方便注册我们小组的小动物上获取的图像， MRI 扫描仪的初始测试将使用标准化测试协议进行。和模拟生理微环境的模型来展示新的潜在效用。系统，它将用于研究肿瘤细胞内和细胞外成分之间的相互作用这项研究将利用自发发育的 MMTV-PyMT 转基因小鼠。 18F-氟脱氧葡萄糖 (FDG)-PET 成像将用于量化增强区域。糖酵解（细胞内成分），而使用多功能三苯甲基探针的 EPR 成像将用于随着增生的发展，在延长的时间点上出现低定量和酸性区域（细胞外成分）由此产生的信息将有助于探索致癌的假设。进展是一个进化过程，并说明了组合 PET-EPRI 扫描仪的独特功能。