Toward layer-specific BOLD fMRI in human cortex at 3T using 3D zoomed-EPI and smallip fast-recovery imaging

使用 3D 缩放 EPI 和 Smallip 快速恢复成像在 3T 下对人类皮质进行层特异性 BOLD fMRI

• 批准号: 9031770
• 负责人: Jon-Fredrik Nielsen
• 金额: $ 18.05万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2018-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9031770
• 关键词: Acceleration; Address; Algorithm Design; Algorithms; Alzheimer' s Disease; Blood; Brain; Brain Mapping; Brain imaging; Clinical; Clinical Research; Communities; Data; Functional Magnetic Resonance Imaging; Future; Goals; Health; Human; Human Volunteers; Image; Imaging Techniques; Lesion; Magnetic Resonance Imaging; Measures; Methods; Microscopic; Microscopy; Multiple Sclerosis; Neurodegenerative Disorders; Neurons; Noise; Physiologic pulse; Process; Protocols documentation; Publishing; Recovery; Research; Resolution; Scanning; Scheme; Signal Transduction; Techniques; Technology; Thick; Time; Venous; Work; area striata; base; blood oxygenation level dependent response; clinical practice; cognitive function; cognitive process; data acquisition; design; functional loss; improved; innovation; magnetic field; neuroimaging; novel; simulation; spatiotemporal; temporal measurement; volunteer

DESCRIPTION (provided by applicant): The goal of this project is to develop a sensitive method for "zoomed", or reduced FOV (rFOV), high-resolution functional magnetic resonance imaging (fMRI) at 3T, and apply it to the study of layer-specific activation across the human cortex. Several groups are currently studying the laminar contributions to the observed fMRI signal, with the goal of relating ob- served fMRI signals to underlying neuronal activity. These studies are generally done at high field with mm to sub-mm resolution across layers. In humans, rFOV imaging at 7T has produced the most detailed depictions to date of laminar functional organization. However, the 7T platform presents certain practical and technical challenges, and is not yet widely available to the neuroimaging community. We propose to develop a protocol for rFOV high-resolution 3D functional brain mapping on 3T clinical scanners with enhanced sensitivity and improved spatio-temporal resolution compared to existing rFOV schemes. 3T MRI is now a mature technology and widely available, and the ability to study laminar functional organization at this field strength, and to differentiate between several underlying neuronal processes based on spatio-temporal fMRI signatures identified in high-resolution laminar studies, would be of fundamental importance to the neuroimaging community. The proposed method could ultimately benefit clinical research and practice as well, e.g., by enabling assessment of the layer-specific functional impact of cortical lesions in neurodegenerative diseases. Our approach contains two key ingredients: First, a novel pulse sequence that encodes functional contrast not only in the transverse magnetization produced by the most recent RF excitation pulse, but also in the steady-state longitudinal magnetization. This permits 3D segmented imaging with short TR, which provides high image quality and time-efficient scanning, without loss of functional contrast relative to conventional 2D multislice BOLD. Second, novel 3D tailored RF pulses for rFOV selection that enable fast non-cartesian data readouts with improved temporal resolution compared to standard approaches. We will perform simulation and human volunteer studies to evaluate the proposed sequence, in terms of functional contrast-to-noise ratio (CNR) across cortical layers and ability to resolve layer-specifc activation and BOLD dynamics (e.g., onset time and activation duration).

描述（由申请人提供）：该项目的目标是开发一种灵敏的方法，用于“缩放”或减少FOV (rFOV)，高分辨率功能磁共振成像（fMRI）在3T，并将其应用于研究人类皮层的层特异性激活。几个小组目前正在研究层流对观察到的fMRI信号的贡献，目的是将观察到的fMRI信号与潜在的神经元活动联系起来。这些研究通常是在高场下进行的，层间分辨率为毫米至亚毫米。在人类中，7T的rFOV成像产生了迄今为止最详细的层流功能组织描述。然而，7T平台提出了一定的实践和技术挑战，尚未广泛应用于神经影像学社区。我们建议在3T临床扫描仪上开发一种rFOV高分辨率3D功能脑成像方案，与现有的rFOV方案相比，该方案具有更高的灵敏度和更高的时空分辨率。3T MRI现在是一项成熟的技术，可以广泛使用，在这种场强下研究层流功能组织的能力，以及基于在高分辨率层流研究中识别的时空fMRI特征来区分几种潜在的神经元过程的能力，对神经影像学社区来说是至关重要的。所提出的方法最终也可能有利于临床研究和实践，例如，通过评估神经退行性疾病中皮层病变对层特异性功能的影响。我们的方法包含两个关键成分：首先，一个新的脉冲序列，不仅在最近的射频激励脉冲产生的横向磁化中编码功能对比，而且在稳态纵向磁化中也编码功能对比。这使得短TR的3D分割成像成为可能，它提供了高质量的图像和高效的扫描时间，而与传统的2D多层BOLD相比，它不会损失功能对比度。其次，用于rFOV选择的新型3D定制RF脉冲，与标准方法相比，可以快速读取非笛卡尔数据，并提高时间分辨率。我们将进行模拟和人类志愿者研究，以评估所提出的序列，包括跨皮质层的功能噪声比（CNR）和解决层特异性激活和BOLD动态（例如，启动时间和激活持续时间）的能力。

项目成果

Pulseq-Graphical Programming Interface: Open source visual environment for prototyping pulse sequences and integrated magnetic resonance imaging algorithm development.

Pulseq 图形编程接口：用于脉冲序列原型设计和集成磁共振成像算法开发的开源视觉环境。

• DOI: 10.1016/j.mri.2018.03.008
• 发表时间: 2018
• 期刊: Magnetic resonance imaging
• 影响因子: 2.5
• 作者: Ravi,KeerthiSravan;Potdar,Sneha;Poojar,Pavan;Reddy,AshokKumar;Kroboth,Stefan;Nielsen,Jon-Fredrik;Zaitsev,Maxim;Venkatesan,Ramesh;Geethanath,Sairam
• 通讯作者: Geethanath,Sairam