MRI Mapping of Venous Oxygenation

静脉氧合的 MRI 测绘

• 批准号: 8303956
• 负责人: ERIC C WONG
• 金额: $ 22.34万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2014-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8303956
• 关键词: Blood; Blood Vessels; Brain; Brain imaging; Carbon Dioxide; Cardiac; Cerebrum; Core-Binding Factor; Decision Making; Dependence; Detection; Development; Energy Metabolism; Financial compensation; Foundations; Functional Imaging; Goals; Head; Hematocrit procedure; Human; Human Volunteers; Image; Ischemic Penumbra; Literature; Magnetic Resonance Imaging; Maps; Measurement; Measures; Metabolism; Methodology; Methods; Noise; Oxygen; Patients; Physiologic pulse; Physiological; Preparation; Residual state; Scanning; Scheme; Signal Transduction; Solid; Source; Stroke; Techniques; Testing; Time; Tissues; Training; Translating; Translational Research; Trees; Validation; Veins; Venous; Work; base; blood oxygen level dependent; brain tissue; human subject; improved; novel; novel strategies; performance tests

DESCRIPTION (provided by applicant): The overall objective of this work is to develop a non-invasive MRI based method for mapping of Oxygen Extraction Fraction (OEF). OEF is thought to be a more specific indicator of penumbra (under perfused but salvageable brain tissue) in stroke than other quantities, and is therefore important for prudent decision-making in the management of stroke patients. OEF is also a key factor in the understanding of cerebral metabolism and contrast mechanisms in BOLD functional imaging. In this work, venous T2 will be used as a surrogate for venous oxygenation, as there is known to be a tight relationship between these two quantities. Recent work has shown that whole-brain measurements of OEF can be made using T2 measurements in the major draining veins of the head. We will develop a new approach that will map T2 and thereby OEF throughout the brain, providing regionally specific information. Our approach is comprised of three modules: 1) selective excitation of moving spins using a novel velocity selective excitation scheme; 2) nulling of arterial signal using inversion tagging of inflowing arterial blood; and 3) mapping of T2 using flow compensated multi-echo, or T2 prepared imaging. We have proposed technical improvements to each of these components, and will implement, test, and optimize these improvements. We will quantify the sources of residual errors in the OEF measurement so that the accuracy of the method is well characterized. At the conclusion of this work, we expect to have an optimized method for non-invasive OEF measurement in the human brain that provides a solid foundation for further technical development and/or translational research. PUBLIC HEALTH RELEVANCE: This project will produce a new non-invasive MRI based method for mapping of the oxygen extraction fraction (OEF) of the brain. OEF is thought to be the best marker for the detection of salvageable brain tissue in stroke patients, and imaging of this measure may significantly improve decision making in the treatment of these patients. In addition, non-invasive OEF mapping will allow for a better understanding of energy metabolism in the brain, as well as the physiological basis of functional brain imaging using blood oxygenation level dependent (BOLD) contrast.

描述（由申请人提供）：这项工作的总体目标是开发一种基于非侵入性 MRI 的氧提取分数 (OEF) 绘图方法。 OEF 被认为是比其他量更具体的中风半暗带（灌注不足但可挽救的脑组织）指标，因此对于中风患者管理中的谨慎决策非常重要。 OEF 也是理解 BOLD 功能成像中脑代谢和对比机制的关键因素。在这项工作中，静脉 T2 将用作静脉氧合的替代值，因为已知这两个量之间存在紧密关系。最近的研究表明，可以使用头部主要引流静脉的 T2 测量来进行 OEF 的全脑测量。我们将开发一种新方法，将 T2 和 OEF 映射到整个大脑，提供区域特定信息。我们的方法由三个模块组成：1）使用新颖的速度选择性激励方案选择性激励移动自旋； 2) 使用流入动脉血的反转标记来消除动脉信号； 3) 使用流量补偿多回波或 T2 准备成像来映射 T2。我们已经对每个组件提出了技术改进，并将实施、测试和优化这些改进。我们将量化 OEF 测量中残余误差的来源，以便很好地表征该方法的准确性。在这项工作结束时，我们期望能够找到一种优化的人脑非侵入性 OEF 测量方法，为进一步的技术开发和/或转化研究提供坚实的基础。 公共健康相关性：该项目将开发一种基于 MRI 的新型非侵入性方法，用于绘制大脑的氧提取分数 (OEF)。 OEF 被认为是检测中风患者可挽救脑组织的最佳标志物，这种测量的成像可以显着改善这些患者的治疗决策。此外，非侵入性 OEF 绘图将有助于更好地了解大脑中的能量代谢，以及使用血氧水平依赖 (BOLD) 对比度进行功能性脑成像的生理基础。