MR PERFUSION IMAGING FOR FUNCTIONAL BRAIN STUDIES

用于脑功能研究的磁共振灌注成像

• 批准号: 6477234
• 负责人: THOMAS EDWARD CONTURO
• 金额: $ 44.75万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-12-21 至 2003-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6477234
• 关键词: baboons; bioimaging /biomedical imaging; biomedical equipment development; blood flow measurement; blood volume; cerebrovascular imaging /visualization; clinical research; computer assisted diagnosis; contrast media; diagnosis design /evaluation; diagnosis quality /standard; functional magnetic resonance imaging; human subject; mathematical model; positron emission tomography; technology /technique development

We proposed to develop quantitative magnetic resonance (MR) methods of imaging cerebral blood flow (CBF) and blood volume (CBV) using combinations of magnitude- and phase-based blood and tissue signals. Quantitative CBV and CBF imaging in the human brain is of significant importance in the evaluation of a number of disease processes, especially those involving longitudinal measurements within and across subjects. Also, it is fundamental in understanding the relationship of brain function to brain metabolism in the normal brain. Compared with the quantitative method of positron emission tomography (PET), MR utilizing bolus administration of gadolinium (Gd), contrast agents has potential advantages of high spatial resolution, high signal- to-signal ratio (SNR), no ionizing radiation, high availability, and lower costs. However, the ability of MR methods to quantitate CBF and CBV has not yet been fully realized. While the magnetic susceptibility effect of bolus Gd injection on change in relaxation rate (deltaR2 or delta R*2 signals) is often used for MR perfusion imaging, these signals are likely dependent on other factors in addition to tissue GD concentration, such as compartmentation (e.g., hematocrit). CBV and CBF quantitations also require measurement of the Gd arterial input function (AIF), where temporal and spatial resolution, SNR, signal linearity with respect to concentration, and response over a wide range of doses and concentrations (dose dynamic range) are critical. We plan to utilize phase shift (delta-phi) signals in conjunction with deltaR2 and deltaR*2 to quantitate CBV and CBF. In model systems, the delta-phi signal is linear and has high SNR and dose dynamic range. As the first Aim, these signal mechanisms will be analyzed theoretically and experimentally in blood and tissue. In the second Aim, signal- concentrations relations will be experimentally determined in blood and tissue. Finally, the validity of quantitative MR CBV and CBF measurements obtained with different signal combinations will be tested against PET in baboons with normal and physiologically-altered flow.

我们建议发展定量磁共振（MR）方法