MRI MEASUREMENT OF RELATIVE CMR02-- VALIDATION USING PET

这项拨款提案，“MRI测量相对CMRO2：使用PET验证”，是R01奖的申请。本课题的目标是：1)在动物模型和人类志愿者中，开发和验证不同生理条件下相对区域脑氧利用代谢率（rcro2）的MR定量成像方法；2)验证神经元调节局灶性脑激活环境下cro2变化与血流动力学之间的关系。该研究的基本假设是，磁共振测量多种血流动力学观测值——BOLD信号、CBF和CBV——将使相对cmo 2的区域和时间评估与啮齿动物和人类的正电子发射断层扫描一致。这些研究将进一步验证脑生理学的一个科学假设：cmor2和CBF的变化总体上表现出一种耦合关系，与血液向脑组织输送氧气的扩散限制模型一致，并得到初步数据的证实。在此框架内，我们将测试MRI信号与潜在物理和生理之间关系的基本假设，并为相对CMRO2和CBF的MR1测量提供确证数据。该研究的成功完成将为脑功能生理学的评估建立一个新的工具，并为这些技术在脑病理学中的应用奠定基础。

This grant proposal, "MRI Measurement of Relative CMRO2: Validation using PET", is an application for an R01 award. The goal of the proposed project is to 1) develop and validate MR methods for quantitative imaging of the relative regional cerebral metabolic rate of oxygen utilization (rCMRO2) under different physiological conditions in animal models and in human volunteers, and 2) validate the relationship between changes in CMRO2 and hemodynamics in the setting of neuronally-modulated focal brain activation. The fundamental hypothesis is that MR measurements of multiple hemodynamic observables - BOLD signal, CBF, and CBV - will enable regional and temporal assessment of relative CMRO2 in agreement with positron emission tomography in rodents and humans. These studies will further test a scientific hypothesis of cerebral physiology: that changes in CMRO2 and CBF exhibit a coupling relationship in general accordance with diffusion-limited models of oxygen delivery from the blood to brain tissue, and as demonstrated by preliminary data. Within this framework we will test the basic assumptions about the relationship between MRI signals and the underlying physics and physiology and provide corroborative data for MR1 measurements of relative CMRO2 and CBF. Successful completion of the proposed studies will establish, a new tool for assessment of cerebral functional physiology and preface the application of these techniques to cerebral pathology.