Non-invasive in-vivo magnetic resonance imaging of microvascular physiology

测量小血管的血流、血管大小和其他生理特性可提供有关组织健康和异常改变性质的宝贵信息。磁共振成像（MRI）等现代医学成像技术提供了一种非侵入性的方法来测量这些特性，但它们都需要注射造影剂。这一要求不允许重复测量，也不允许非常年幼的儿童和其他敏感对象使用。在本提案中，我们开发了一个真正的非侵入性MRI平台，以精细的空间细节测量小血管的结构和功能，而无需注射造影剂。这是一项新颖的变革性技术，将极大地扩展与小血管相关的基础和应用研究的范围。

Measuring blood flow, vessel size, and other physiological properties of small blood vessels provides valuable information about the health of tissue and the nature of abnormal alterations. Modern medical imaging techniques such as magnetic resonance imaging (MRI) provide a non-invasive way to measure these properties, but they all require the injection of contrast agents. This requirement precludes repeated measurements and is not accessible to very young children and other sensitive subjects. In this proposal, we develop a truly non-invasive MRI platform to measure small vessel structure and function with fine spatial detail - without injecting contrast. This is a novel and transformative technology that will greatly expand the scope of basic and applied research related to small blood vessels. We propose for this new non-invasive MRI approach the use of modified inhaled air, which is safe for everyone, as a substitute for contrast agent injection. To build the initial technical foundation, this proposal will develop the capability to measure the flow, volume, and size of small blood vessels. What is novel in this research is the use and integration of physiology with concepts in imaging, physics, and mathematics. This technology will provide the unique ability to measure structural and functional parameters with fine spatial detail and without contrast injection. No current technique provides similar breadth of information or fine delineation. The impact of this research spans multiple disciplines. It will establish a new direction in engineering and the physical sciences for non-invasive microvascular imaging technology development. It will improve basic biomedical research into studies of normal and disease processes, including drug discoveries for cancer, ischemia, and other vessel-related conditions. The benefits of a repeatable, universally accessible, and truly non-invasive imaging technology will ultimately be reaped for improved disease diagnosis and treatment in humans.