Acquisition technology for in vivo functional and structural MR imaging at the mesoscopic scale.

介观尺度体内功能和结构 MR 成像的采集技术。

• 批准号: 10224851
• 负责人: Kawin Setsompop
• 金额: $ 25.64万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10224851
• 关键词: Acceleration; Algorithms; Animal Model; Animals; Architecture; Biological; Blood Vessels; Brain; Brain imaging; Cell Nucleus; Cells; Cerebrum; Clinical; Complement; Cortical Column; Data; Data Set; Development; Diffusion; Diffusion Magnetic Resonance Imaging; Frequencies; Functional Magnetic Resonance Imaging; Gold; Human; Image; Investigation; Joints; Machine Learning; Magnetic Resonance Imaging; Microscopic; Microscopy; Morphologic artifacts; Motion; Neurons; Optics; Performance; Peripheral Nerve Stimulation; Physiologic pulse; Play; Relaxation; Resolution; Role; SKI gene; Sampling; Scanning; Scheme; Sensitivity and Specificity; Slice; Space Models; Specificity; Speed; Structure; Surface; Techniques; Technology; Time; Variant; Veins; animal imaging; base; denoising; design; gray matter; human imaging; improved; in vivo; in vivo imaging; insight; instrumentation; machine learning algorithm; neural circuit; novel; novel strategies; performance tests; preservation; programs; reconstruction; spatiotemporal; technology development; temporal measurement; tool

Significant strides have been made in microscopic brain imaging of animal models and ex vivo samples, led by advances in optical microscopy and new tools for manipulation of neural circuitry and targeted stimulation; enabling us to gain new insights into neuronal cells and circuits functions at this fine scale. Concurrent to these developments, in vivo non-invasive human brain imaging, particularly through MRI, has also undergone significant advancement. This has allowed it to collect rich functional and structural information at the macroscale quickly, and also aid in its push towards higher spatial resolution, where imaging at the mesoscopic scale is starting to become feasible. Nonetheless, critical barriers remain in achieving adequate specificity and sensitivity at this scale. The ability to image more precisely at the mesoscale both structurally and functionally with MRI will play a critical role to bridge the gap and transfer our improved understanding at the microscale with animal and ex vivo studies to macroscale human imaging that are performed in large scale studies and in clinical settings. This project will create a program for MR technology development to overcome current “encoding limits” in MRI to achieve in vivo imaging at the mesoscopic scale: diffusion, functional, and structural imaging of the human brain at the 400–600 µm isotropic voxel size with high sensitivity and high spatial accuracy. This will push in vivo MRI from the macro-scale toward the meso-scale of cerebral cortical columns and layers and subcortical nuclei to transfer new insights from invasive animal and post mortem micro-scale imaging to non-invasive human imaging. Because fundamental modules of brain organization can be observed in the meso-scale architecture, this project will allow for in vivo investigation at relevant spatial scales with sufficient coverage. We will undertake a synergistic ‘from-the-ground-up’ development that combines novel encoding and reconstruction strategies with newly-available instrumentation to achieve high imaging fidelity and sensitivity at the target resolution. SNR-efficient volumetric and continuous acquisitions along with highly-accelerated spatio-temporal controlled-aliasing encoding will be developed. New approaches to image encoding will be created that utilize a recently-introduced combined RF and B0 shim-array technology, not only for its original intended purpose of reducing B0 inhomogeneity, but also to complement conventional encoding schemes to increase acceleration performance, improve robustness, and achieve large artifacts mitigation, particularly for multi-shot EPI. Synergistic reconstruction schemes will also be developed using emerging concepts in low-rank and multi-dimensional sub-space modeling combined with powerful Machine Learning (ML) algorithms. The proposed time-resolved reconstruction of both functional and structural data will provide a new, rich imaging dataset with hundreds of TEs and TIs from a single scan. With this approach, the detrimental image blurring from relaxation effects and distortion from B0 inhomogeneity, will also be removed to create sharp, high-fidelity datasets.

在动物模型和离体样本的显微脑成像方面取得了重大进展 光学显微镜的进步以及用于操纵神经回路和定向刺激的新工具； 使我们能够在如此精细的尺度上获得对神经元细胞和电路功能的新见解。与这些同时进行 随着技术的发展，体内非侵入性人脑成像，特别是通过 MRI 进行的成像，也取得了长足的进步。 显着进步。这使得它能够在宏观尺度上收集丰富的功能和结构信息 快速，并且还有助于推动更高的空间分辨率，其中介观尺度的成像是 开始变得可行。尽管如此，在实现足够的特异性和敏感性方面仍然存在关键障碍 在这个规模上。通过 MRI 在结构和功能上更精确地在介观尺度上成像的能力将 在弥合差距和传递我们在微观尺度上对动物和动物的更好理解方面发挥着关键作用 在大规模研究和临床环境中进行的宏观人体成像的离体研究。 该项目将为 MR 技术开发创建一个计划，以克服 MRI 当前的“编码限制” 实现细观尺度的体内成像：人体的扩散、功能和结构成像 大脑在 400–600 µm 各向同性体素尺寸下具有高灵敏度和高空间精度。这将推入 从宏观尺度到大脑皮质柱、层和皮质下的中观尺度的体内 MRI 细胞核将新见解从侵入性动物和死后微尺度成像转移到非侵入性 人体成像。因为大脑组织的基本模块可以在中观尺度上观察到 建筑方面，该项目将允许在具有足够覆盖范围的相关空间尺度上进行体内研究。 我们将进行“从头开始”的协同开发，将新颖的编码和 使用新可用的仪器进行重建策略，以实现高成像保真度和灵敏度 目标分辨率。高效信噪比的体积和连续采集以及高度加速 将开发时空受控混叠编码。图像编码的新方法将是 创建利用最近推出的组合 RF 和 B0 匀场阵列技术，不仅是为了其原始的 减少 B0 不均匀性的预期目的，同时也是对传统编码方案的补充 提高加速性能、提高鲁棒性并实现大伪影缓解，特别是对于 多次 EPI。协同重建方案也将利用低阶中的新兴概念来开发 多维子空间建模与强大的机器学习（ML）算法相结合。这 提出的功能和结构数据的时间分辨重建将提供新的、丰富的成像 一次扫描包含数百个 TE 和 TI 的数据集。通过这种方法，有害的图像模糊 来自松弛效应和 B0 不均匀性失真的影响也将被消除，以创建清晰的高保真度 数据集。