Magnetic Resonance Elastography

 描述（由申请人提供）：许多疾病过程导致组织机械特性的深刻变化，为开发用于诊断目的的测量这些特性的技术提供了动力。此外，在过去的十年中，人们越来越认识到组织基质力学对细胞功能的重要性。细胞通过机械转导和细胞骨架重塑对其基质环境的动态和静态特性作出反应。现在已知，机械生物学在许多疾病过程的起源和演变中具有重要作用，包括纤维化和癌症。这项研究的目标是开发先进的基于MRI的技术，用于定量评估组织的机械性能，并探索和转化高影响力的临床和研究应用。MR弹性成像（MRE）基于传播机械波反映其介质属性的原理。剪切波是在体内产生的，并用MRI技术成像，该技术具有描绘小至100纳米的周期运动的卓越能力。用反演算法处理数据，以提供定量描述机械性能（如复合剪切模量）的横截面图像。在上一个资助周期中，在该资助下开发的肝脏MRE技术已成功转化为广泛的临床实践，目前已在全球数百家医疗机构用于患者护理。肝纤维化是一个重要的健康问题，在美国人口中的患病率不断上升。对于许多患者，磁共振成像提供了一个更安全，更舒适，更便宜的替代肝活检诊断这种情况。研究还揭示了许多其他有前途的应用，包括非侵入性诊断其他器官的纤维化和炎症，检测和表征恶性肿瘤，提供新的生物标志物来评估脑部疾病，并作为组织和器官尺度的基础研究机械生物学的工具。与上一个赠款周期一样，工作的主要重点将继续是先进技术的开发，以便在这一有前途的领域进行进一步的基础和临床研究，以及进行试点研究以确定临床应用，并制定实用的协议，以便验证并最终将MRE应用于临床实践。该研究计划涉及理论工作，基本MRI脉冲序列开发，设备工程和正常和患者志愿者的协议测试研究。将实施和评估创新方法，用于在组织中产生机械波，获取图像数据，并处理以生成描述以前无法获得的生物标志物的定量图像。这些技术将被集成到协议中，可以与其他研究人员共享，并用于探索有前途的应用的实用性和价值。

 DESCRIPTION (provided by applicant): Many disease processes cause profound changes in the mechanical properties of tissue, providing motivation for developing technologies to measure these properties for diagnostic purposes. In addition, over the last decade there has been growing awareness of the importance of tissue matrix mechanics on cellular function. Cells react to the dynamic and static properties of their matrix environment through mechanotransduction and cytoskeletal remodeling. It is now known that mechanobiology has an important role in the origin and evolution of many disease processes, including fibrosis and cancer. The goal of this research is to develop advanced MRI-based technologies for quantitatively assessing the mechanical properties of tissue and to explore and translate high-impact clinical and research applications. MR Elastography (MRE) is based on the principle that propagating mechanical waves reflect the properties of their medium. Shear waves are generated in the body and imaged with MRI techniques that have the remarkable ability to depict cyclic motions as small as 100 nanometers. The data are processed with inversion algorithms to provide cross-sectional images quantitatively depicting mechanical properties such as the complex shear modulus. In the last grant cycle, the hepatic MRE technology developed under this grant was successfully translated into wide clinical practice and is now used in patient care at hundreds of medical facilities around the world. Liver fibrosis is an important health problem with a rising prevalence in the US population. For many patients, MRE provides a safer, more comfortable, and less expensive alternative to liver biopsy for diagnosing this condition. Research has revealed many other promising applications, including noninvasive diagnosis of fibrosis and inflammation in other organs, detection and characterization of malignancies, providing new biomarkers to assess brain disease, and as a tool in basic research mechanobiology at the tissue and organ scales. As in the last grant cycle, the primary focus of the work will continue to be advanced technology development, to enable further basic and clinical research in this promising field, as well as to conduct pilot studies to identify clincal applications, and to develop practical protocols that will allow validation and eventual translatio to MRE to clinical practice. The research plan involves theoretical work, basic MRI pulse sequence development, device engineering, and protocol testing studies with normal and patient volunteers. Innovative approaches will be implemented and evaluated for generating mechanical waves in tissue, acquiring image data, and processing to generate quantitative images depicting previously inaccessible biomarkers. These technologies will be integrated into protocols that can be shared with other investigators and used to explore the practicality and value of promising applications.