Noninvasive MR imaging of cerebral arterial blood volume in humans

人体脑动脉血容量的无创 MR 成像

• 批准号: 7961928
• 负责人: SEONG KIM
• 金额: $ 21.92万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7961928
• 关键词: Animals; Blood; Blood Vessels; Blood Volume; Blood capillaries; Blood flow; Cerebrovascular Circulation; Cerebrum; Contrast Media; Diagnosis; Fibrosis; Functional Magnetic Resonance Imaging; Future; Gadolinium; Goals; Gold; Human; Image; Imaging Techniques; Injection of therapeutic agent; Investigation; Label; Laboratories; Magnetic Resonance Imaging; Maps; Measurement; Measures; Methods; Neurons; Physiological; Rattus; Regulation; Relative (related person); Research; Signal Transduction; Site; Specificity; Spin Labels; Techniques; Testing; Tissue Viability; Tissues; Translations; Vascular Diseases; Venous; Water; animal data; awake; base; blood oxygen level dependent; capillary; improved; indexing; insight; magnetic field; neural stimulation; public health relevance; relating to nervous system; response; success

DESCRIPTION (provided by applicant): Regional cerebral blood volume (CBV) and its dynamic change induced by neural activity are critical indices for evaluating tissue viability and function. Routine magnetic resonance imaging (MRI) of CBV in humans currently requires injection of gadolinium-based blood contrast agents, hampering repeated measurements and potentially causing nephrogenic systemic fibrosis. Therefore, alternative non-invasive techniques are required for CBV mapping in humans. Importantly, compartment-specific CBV measurements will be crucial to obtain insight into blood flow regulation during physiological responses, because arterial vessels dilate and constrict to actively control cerebral blood flow (CBF), while venous vessels respond passively. In this application, we propose in humans at 3 Tesla to evaluate and implement non-invasive, arterial CBV measurement techniques without contrast agents, to perform quantitative mapping of baseline arterial CBV, and to determine its relative change during stimulation. The hypotheses to be tested are to determine whether quantitative arterial CBV can be reliably mapped in humans by non-invasive MRI techniques and to determine whether the arterial CBV change is significant during neural activity in humans. Baseline arterial CBV can be measured by our recent arterial spin-labeling techniques, which have been successfully applied to quantitatively map arterial CBV and CBF in animals. Translation to 3-T awake human studies necessitates consideration of differences in species, physiological conditions, and magnetic field strengths. Therefore we will carefully evaluate and optimize human techniques for arterial CBV measurement, and examine the consistency of arterial CBV quantification. During stimulation, it is often assumed that the arterial CBV change is minimal and therefore can be ignored in functional MRI (fMRI) studies. However, this notion has recently been challenged by our animal studies showing that the arterial CBV increase is the dominant contribution to the total CBV response. Thus, we propose to apply this arterial CBV-based fMRI technique to humans to determine dynamic changes and spatial specificity of arterial CBV and 'true' BOLD signals during neural stimulation. The goal of these investigations is to implement non-invasive blood volume mapping techniques for routine human imaging without the injection of contrast agents, which will enable future diagnosis and study of vascular disease. PUBLIC HEALTH RELEVANCE: Develop noval non-invasive MR blood volume imaging techniques and to measure baseline cerebral blood volume and its changes during stimulation in humans.

描述（由申请人提供）：区域脑血体积（CBV）及其由神经活动引起的动态变化是评估组织生存力和功能的关键指标。人类中CBV的常规磁共振成像（MRI）目前需要注射基于gadolinium的血液对比剂，阻碍了重复测量并可能引起肾病性全身性纤维化。因此，人类中的CBV映射需要替代性非侵入性技术。重要的是，室特异性的CBV测量对于在生理反应过程中了解血流调节至关重要，因为动脉血管扩张并收缩以积极控制脑血流（CBF），而静脉血管反应被动反应。在此应用中，我们在3个特斯拉的人类中提议评估和实施无侵入性的动脉CBV测量技术，而无需对比度，以对基线动脉CBV进行定量映射，并确定其在刺激过程中的相对变化。要测试的假设是为了确定通过非侵入性MRI技术在人类中可靠地映射定量动脉CBV，并确定在人类神经活动期间动脉CBV变化是否显着。基线动脉CBV可以通过我们最近的动脉自旋标记技术来测量，这些技术已成功应用于动物中的动脉CBV和CBF。转化为3-T清醒人类研究需要考虑物种，生理条件和磁场强度的差异。因此，我们将仔细评估和优化人类的动脉CBV测量技术，并检查动脉CBV定量的一致性。在刺激过程中，通常假定动脉CBV的变化很小，因此在功能性MRI（fMRI）研究中可以忽略。但是，我们的动物研究最近挑战了这一观念，表明动脉CBV的增加是对总CBV反应的主要贡献。因此，我们建议将这种基于动脉CBV的FMRI技术应用于人类，以确定动脉CBV的动态变化和空间特异性和神经刺激过程中“ True” BOLD信号。这些研究的目的是实施非侵入性血量映射技术，以便在不注射造影剂的情况下进行常规的人类成像，这将使未来的诊断和研究血管疾病。 公共卫生相关性：开发新的非侵入性MR血液体积成像技术，并测量人类刺激期间的基线脑血体积及其变化。