A magnetic particle imager (MPI) for functional brain imaging in humans

用于人类脑功能成像的磁粒子成像仪 (MPI)

基本信息

批准号：
9418281
负责人：
Lawrence L Wald
金额：
$ 101.01万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-09-26 至 2022-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9418281
关键词：
Animals Architecture Area Base of the Brain Biomedical Engineering Blood Brain Brain imaging Detection Development Devices Disease Electromagnetics Engineering Exercise Foundations Functional Imaging Functional Magnetic Resonance Imaging Generations Geometry Goals Grant Head Health Human Hypercapnia Image Imaging Device Individual Injectable Investigation Iron Label Laboratories Macaca Macaca mulatta Magnetic Resonance Magnetic Resonance Imaging Magnetism Methodology Methods Modality Modeling Monitor Monoclonal Antibody R24 Neurons Neurosciences Noise Oxidants Pattern Performance Phase Protocols documentation Protons Relaxation Resolution Resources Rest Risk Rodent Rodent Model Safety Scanning Source Specialist Structure System Techniques Technology Testing Time Validation Visual Cortex Work awake base cerebral blood volume cerebral capillary cerebral hemodynamics data acquisition design detector experimental study ferumoxytol hemodynamics human imaging image reconstruction imaging modality improved instrument iron oxide model building nanoparticle next generation nonhuman primate operation particle programs response simulation tool visual motor

项目摘要

In this U01 grant we propose a 5 year engineering development effort to advance Magnetic Particle Imaging (MPI) to replace MRI as the next-generation functional brain imaging tool for human neuroscience. MPI is a young but extremely promising technology that uses the non-linear magnetic response of ironoxide nanoparticles to localize their presence in the body. MPI directly detects the nanoparticle's magnetization rather than using secondary effects on the Magnetic Resonance relaxation times. Thus, while MPI and MRI share many technologies, the MPI method does not use the MR phenomena in any way. Our plan is to detect the activation-induced and resting-state changes in the iron-oxide concentration in the cerebral capillary network by monitoring the local iron oxide concentration (and thus local Cerebral Blood Volume, CBV). This CBV-contrast source is well- proven in animal and human fMRI studies which detect CBV changes by MRI using the same iron- oxide agents, but indirectly. But, by developing MPI as the detection modality, we show that there is a potential 10-fold increase in the contrast-to-noise ratio (CNR) of human neuronal activation. In the planning grant stage, we analyzed multiple potential MPI scanner designs for humans and settled on a Field-Free-Line geometry. We developed the simulation tools to model the performance of a human sized instrument. Additionally, we validated our modeling by building and testing a small, rodent-scale MPI detector in our lab at MGH. Using this device, we showed the first ever demonstration of functional imaging with MPI using a rodent hypercapnia model. In this U01 phase we seek the resources to construct and validate the human scale, rotating FFL-style MPI device analyzed in the planning grant. After construction, we will validate its performance in phantom studies, and also in an awake-behaving macaque model that we have previously used for fMRI studies. Finally, we will validate the performance of the device in limited human fMPI studies. By developing a new and more sensitive detection methodology for functional human imaging, we hope to add a powerful new non-invasive methods to the tools available to neuroscientists studying the human brain in health and disease.

在这项 U01 拨款中，我们提出了为期 5 年的工程开发工作，以推进磁性技术的发展粒子成像（MPI）将取代 MRI 成为人类下一代功能性脑成像工具神经科学。 MPI 是一项年轻但极具前景的技术，它使用非线性磁氧化铁纳米颗粒的反应来定位它们在体内的存在。 MPI 直接检测纳米粒子的磁化而不是利用磁共振的二次效应放松时间。因此，虽然 MPI 和 MRI 共享许多技术，但 MPI 方法不使用 MR 现象以任何方式。我们的计划是检测激活诱导和静息状态通过监测局部铁来改变脑毛细血管网络中的氧化铁浓度氧化物浓度（以及局部脑血量，CBV）。这个 CBV 对比源非常好已在动物和人类 fMRI 研究中得到证实，这些研究使用相同的铁离子通过 MRI 检测 CBV 变化氧化物试剂，但间接。但是，通过开发 MPI 作为检测方式，我们表明存在人类神经元激活的对比噪声比 (CNR) 可能增加 10 倍。在规划拨款阶段，我们分析了多种潜在的人类 MPI 扫描仪设计，确定了无场线几何形状。我们开发了模拟工具来模拟性能一个人体大小的仪器。此外，我们通过构建和测试一个小型的、 MGH 实验室中的啮齿动物规模 MPI 探测器。使用这个设备，我们展示了有史以来第一个使用啮齿动物高碳酸血症模型演示 MPI 功能成像。在这个U01阶段我们寻求资源来构建和验证人体规模的旋转 FFL 式 MPI 设备在规划补助金中进行了分析。构建完成后，我们将在幻影中验证其性能研究，以及我们之前用于功能磁共振成像的清醒行为猕猴模型研究。最后，我们将在有限的人类 fMPI 研究中验证该设备的性能。通过开发一种新的、更灵敏的人体功能成像检测方法，我们希望为神经科学家研究可用的工具添加一种强大的新的非侵入性方法健康和疾病中的人脑。