Localized measurement and mapping of tissue nonlinear elasticity

组织非线性弹性的局部测量和绘图

基本信息

批准号：
9297301
负责人：
Azra Alizad
金额：
$ 23.48万
依托单位：
MAYO CLINIC ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-07-01 至 2019-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9297301
关键词：
Acoustics Adipose tissue Behavior Benign Biological Markers Breast Clinic Data Development Diagnostic Diagnostic Imaging Diagnostic Procedure Effectiveness Elasticity Evaluation Fibroadenoma Focused Ultrasound Future Geometry Goals Hydrostatic Pressure Image Investigation Laboratories Lesion Magnetic Resonance Imaging Malignant - descriptor Malignant Neoplasms Mammary Gland Parenchyma Mass in breast Measurement Measures Mechanics Medicine Methodology Methods Modality Modulus Monitor Organ Outcome Study Palpation Pathologic Pathology Performance Pilot Projects Property Publishing Radiation Research Resolution Sampling Sensitivity and Specificity Specificity Speed Techniques Testing Time Tissue Sample Tissues Translations Ultrasonography Variant animal tissue base breast imaging diagnostic biomarker elastography imaging modality improved in vivo infiltrating duct carcinoma innovation interest member novel novel diagnostics physical property radiation response response shear stress skills soft tissue theories tissue phantom tool virtual

项目摘要

Abstract Palpation has been used for hundreds of years in medicine to differentiate various types of tissues and masses within tissue. In technical terms, palpation can be defined as deformation of tissue in response to a force, which in linear mechanics is defined as tissue elasticity. The concept of tissue elasticity i.e. elastography has been the subject of intense investigations in the past two decades. However, recent studies have shown that tissue behaves nonlinearly at larger strains, whereby the nonlinear elasticity of tissue may carry important diagnostic information. The long-term objective of this research is the development of a novel diagnostic technique that (i) makes use of the acoustic radiation force (ARF) for noninvasive tissue interrogation, and (ii) deploys a novel coefficient of nonlinear tissue elasticity as a biomarker that is sensitive to tissue type. One possible application of the method, initiated in this study, is the differentiation of breast masses; however, the proposed method may find applications in other organs. The proposed study is made possible by the recent discovery by our research team that the magnitude of the ARF in soft tissues depends linearly on a particular coefficient of nonlinear tissue elasticity, hereon denoted by C – that quantifies the gain in shear wave speed due to increasing hydrostatic pressure. The basic idea behind the method is to act upon tissue by the ARF at a point of interest (e.g. inside a breast mass) and to monitor the ARF-generated generated shear waves via ultrasound. In this setting, the nonlinear modulus C can be computed from the amplitude of the observed shear waves — a claim that is supported by our preliminary data on tissue-mimicking phantoms and animal tissues. The proposed approach to nonlinear tissue elastography is novel in that: (a) it focuses on the volumetric-shear modulus C that has eluded previous studies, and (b) it enables, for the first time, local evaluation of nonlinear tissue elasticity with a spatial resolution given by the size of the focal region (order of mm). This makes it possible to locally measure C over the volume of the focal region using the ARF. For this reason, the proposed method is hereon referred to as nonlinear C-Elastography (CE). To assess the effectiveness of CE, we first propose to create well-characterized phantoms with (tissue-mimicking) lesions and create their C-images to be compared with the respective linear (e.g. shear modulus) elastograms. The last stage of our study would focus on the ex-vivo testing of breast masses, through which we will be able to correlate the CE results to tissue pathology and assess the overall effectiveness of CE. Successful completion of this research will spur the development of a noninvasive, diagnostic tool that may have significant impact in early differentiation of breast masses and potentially pathologies in other organs.

抽象的触诊已在医学领域使用了数百年，以区分各种类型的组织和质量在组织内。用技术术语，触诊可以定义为响应力的组织变形，在线性力学中，将其定义为组织弹性。组织弹性的概念，即弹性学具有在过去的二十年中，我们是激烈调查的主题。但是，最近的研究表明组织在较大的菌株上表现非线性，因此组织的非线性弹性可能具有重要诊断信息。这项研究的长期目标是开发新型诊断（i）利用声学辐射力（ARF）进行无创组织审讯的技术，（ii）部署一种新型的非线性组织弹性系数，作为对组织类型敏感的生物标志物。一在本研究中启动的该方法的可能应用是乳腺肿块的分化。但是，建议的方法可以在其他器官中找到应用。拟议的研究是由最近的我们的研究团队发现，软组织中ARF的大小是线性取决于特定的非线性组织弹性的系数，以c表示量子，从而量化了剪切波速度的增益由于静水压力的增加。该方法背后的基本思想是在A处由ARF作用于组织感兴趣的点（例如在乳房内），并通过超声波。在这种情况下，可以从观察到的剪切的放大器计算非线性模量C 波浪 - 我们关于模拟组织幻象和动物组织的初步数据支持的主张。提出的非线性组织弹性图的方法是新颖的：（a）它重点放在体积剪切上模量c的模量c，并且（b）首次实现非线性的本地评估组织弹性，具有由焦点区域的大小（mm的级数）给出的空间分辨率。这使它变得如此使用ARF可以在焦点区域的体积上局部测量C。因此，提议方法在此称为非线性C弹性图（CE）。为了评估CE的有效性，我们首先提议创建具有（模拟组织）病变并创建其C形图像的特征良好的幻象与相对线性（例如剪切模量）弹性图相比。我们研究的最后阶段将重点关于乳腺肿块的活体测试，我们将能够将CE结果与组织相关联病理和评估CE的总体有效性。这项研究的成功完成将刺激开发非侵入性的诊断工具，可能会对早期分化产生重大影响乳房肿块和其他器官的潜在病理。