Development of a Tissue-Specific fMRI Technique

组织特异性功能磁共振成像技术的发展

• 批准号: 7508171
• 负责人: Tao Jin
• 金额: $ 20.8万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-05-01 至 2011-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7508171
• 关键词: Blood; Blood Vessels; Blood Volume; Brain Mapping; Brain imaging; Cells; Cerebrum; Characteristics; Clinical; Complex; Coupling; Data; Development; Felis catus; Functional Magnetic Resonance Imaging; Human; Image; Imaging Techniques; Investigation; Maps; Measures; Metabolic; Modeling; Neurons; Neurosciences Research; Photic Stimulation; Physiologic pulse; Physiological; Property; Relaxation; Research; Resolution; Signal Transduction; Site; Source; Specificity; Techniques; Testing; Time; Tissues; Visual Cortex; Water; base; blood oxygen level dependent; brain tissue; density; hemodynamics; improved; novel; public health relevance; relating to nervous system; response; tool

DESCRIPTION (provided by applicant): Most current functional magnetic resonance imaging (fMRI) techniques measure the change in water T2* or T2 caused by blood oxygenation-level dependent (BOLD) contrast, which are based on the hemodynamic responses to neuronal activity. However, the coupling between neuronal activity and hemodynamics is complex, and the spatial and temporal resolutions of hemodynamic-based fMRI are intrinsically limited by properties of the vasculature. In order to improve the spatial specificity and to obtain a faster temporal response, the imaging signal should directly originate from tissue (i.e., neuronal cells), rather than from blood vessels. In this project, a novel fMRI technique based on tissue T1rho will be developed, and its spatial and temporal characteristics will be examined. T1rho is the spin-lattice relaxation time in the rotating frame during an applied spin-locking pulse, and has been found to be sensitive to intracellular pH level as well as macromolecular composition and density. This tissue T1rho fMRI contrast is presumably induced by an acidification of neuronal cells during activation, and is expected to be faster, with spatial origins more specific to sites of neural activity than hemodynamic-based fMRI. Thus, tissue T1rho fMRI contrast may greatly improve the accuracy of noninvasive functional brain mapping in basic and clinical neuroscience research. PUBLIC HEALTH RELEVANCE: This investigation aims to develop a novel non-invasive brain imaging technique that can be faster and more accurate than conventional techniques.

描述（由申请人提供）：大多数当前的功能磁共振成像（fMRI）技术测量由血氧水平依赖性（BOLD）对比度引起的水T2*或T2的变化，其基于对神经元活动的血流动力学反应。然而，神经元活动和血流动力学之间的耦合是复杂的，基于血流动力学的功能磁共振成像的空间和时间分辨率本质上受到脉管系统特性的限制。为了提高空间特异性并获得更快的时间响应，成像信号应直接源自组织（即神经元细胞），而不是来自血管。在该项目中，将开发一种基于组织 T1rho 的新型功能磁共振成像技术，并检查其空间和时间特性。 T1rho 是施加自旋锁定脉冲期间旋转框架中的自旋晶格弛豫时间，并且已被发现对细胞内 pH 水平以及大分子组成和密度敏感。这种组织 T1rho fMRI 对比可能是由激活期间神经元细胞的酸化引起的，并且预计速度更快，与基于血流动力学的 fMRI 相比，空间起源更具体于神经活动部位。因此，组织 T1rho fMRI 对比可以极大地提高基础和临床神经科学研究中无创功能性脑图的准确性。公共健康相关性：这项研究旨在开发一种新型非侵入性脑成像技术，该技术比传统技术更快、更准确。