Measurement of Renal Viscoelastic Properties with Ultrasound

超声测量肾粘弹特性

• 批准号: 9924519
• 负责人: Matthew William Urban
• 金额: $ 61.33万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-07 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9924519
• 关键词: Achievement; Acoustics; Affect; Allografting; Atrophic; Biopsy; Chronic Kidney Failure; Clinic; Clinical; Creatinine; Data; Diagnosis; Diagnostic; Disease; Doppler Ultrasound; End stage renal failure; Equation; Evaluation; Fibrosis; Foundations; Frequencies; Funding; Glomerular Filtration Rate; Goals; Gold; Graft Rejection; Graft Survival; Grant; Health; Health Care Costs; Hemodialysis; Inflammation; Inflammatory; Kidney; Kidney Diseases; Kidney Failure; Kidney Transplantation; Knowledge; Laboratories; Measurement; Measures; Medical; Medical Imaging; Methods; Modeling; Modulus; Monitor; Motion; Nature; Pathology; Patient Monitoring; Patient-Focused Outcomes; Patients; Physiological; Procedures; Process; Progress Reports; Property; Protocols documentation; Publications; Quality of life; Radiation; Renal function; Research; Research Proposals; Risk; Serum; Statistical Data Interpretation; Stress; Structure; Survival Rate; Techniques; Testing; Therapeutic Intervention; Tissue Differentiation; Tissues; Translating; Translations; Tubular formation; Ultrasonography; Waiting Lists; attenuation; base; clinical practice; clinical translation; cost; diagnosis standard; diagnostic accuracy; elastography; experimental study; imaging approach; imaging modality; improved; insight; interstitial; kidney allograft; kidney biopsy; mechanical properties; non-invasive imaging; patient subsets; programs; public health relevance; screening; soft tissue; standard of care; time use; tool; treatment response; viscoelasticity

ABSTRACT/SUMMARY Background: Chronic kidney disease (CKD) encompasses a long-term decrease in function of the kidneys. CKD can progress to kidney failure or end-stage renal disease (ESRD), which is treated by hemodialysis or kidney transplant. Patient and renal graft survival rates have increased over the past two decades, but long- term survival of grafts is still an issue. Renal biopsy is the gold standard for diagnosis of kidney health, but is an invasive procedure, cannot be used frequently, and can cause complications. Noninvasive indicators of kidney disease including levels of serum creatinine, glomerular filtration rate, and classical medical imaging can provide certain insights into kidney disease state. Elasticity imaging methods can discriminate healthy versus diseased tissue based on different parameters measured in the tissue. We have found in the previous cycle of this grant that certain elastographic parameters are sensitive to different structural or physiological changes in renal allografts. Linear and nonlinear elastic mechanical properties were found to be sensitive to the presence of interstitial fibrosis while viscoelastic parameters were sensitive to inflammatory processes and tubular atrophy. Based on these findings, we propose the use of quantitative, noninvasive methods to perform a comprehensive multi-parametric elastographic evaluation of renal allografts to evaluate health of the transplanted kidney. Methods: Ultrasound shear wave-based methods use acoustic radiation force to “push” the tissue and create shear waves. Ultrasound-based methods are used to detect the propagation of the shear waves through the tissue. The propagation velocity of the shear waves can be modified by several parameters including the elastic, viscoelastic, and nonlinear, mechanical properties in the tissue. We will use shear wave elastography (SWE) to measure elastic properties in the kidney using time-of-flight methods. Viscoelastic properties will be measured using a model-based approach by fitting shear wave velocity dispersion to rheological models or a model-free approach that involves extracting measurements of shear wave velocity and attenuation at various frequencies. Lastly, we will use a method called acoustoelasticity, which combines compression of the renal allograft and SWE measurements to estimate the nonlinear elastic modulus from shear modulus data obtained at various levels of applied stress. The parameters extracted from these measurements will be compared with structural (biopsy) and functional measures of kidney health (serum creatinine, estimated glomerular filtration rate, and Doppler ultrasound results) to elucidate how allograft disease changes these parameters. Establishing these relationships will provide a strong foundation for translating these elastographic measurement methods forward for widespread clinical use for assessment of renal allografts. The noninvasive nature of SWE measurements, available on many clinical ultrasound scanners, make them a strong candidate as a tool for reducing the number of biopsies, and to be used for frequent quantitative assessment and monitoring of patients’ responses to treatment, which will lead to reduced healthcare costs and potentially improved patient outcomes. To accomplish these objectives, we propose the following Specific Aims. Aims: 1) Evaluate the use of SWE to measure elastic mechanical properties for the noninvasive assessment of structural and functional changes in renal allografts. 2) Evaluate the use of SWE to measure viscoelastic mechanical properties to assess renal allograft fibrosis, inflammation, and function. 3) Evaluate the use of acoustoelasticity to measure nonlinear elastic mechanical properties to assess pathology and functional changes in renal allografts.

摘要/摘要 背景：慢性肾脏疾病（CKD）涵盖了肾脏功能的长期降低。 CKD可以发展为肾功能衰竭或终末期肾脏疾病（ESRD），该疾病通过血液透析或 肾脏移植。在过去的二十年中，患者和肾移植物存活率有所提高，但长期 移植物的期限仍然是一个问题。肾脏活检是诊断肾脏健康的黄金标准，但 一种侵入性程序，不能经常使用，并且可能引起并发症。无创的指标 肾脏疾病包括血清肌酐水平，肾小球滤过率和经典医学成像 可以对肾脏疾病状态提供某些见解。弹性成像方法可以区分健康 基于组织中测得的不同参数而不是解剖组织。我们在上一个 这项授予的循环，即某些弹性参数对不同的结构或生理敏感 肾脏同种异体移植的变化。发现线性和非线性弹性机械性能对 粘弹性参数对炎症过程和 结节萎缩。基于这些发现，我们建议使用定量，无创方法执行 肾脏专辑的全面多参数弹性评估，以评估 移植的肾脏。方法：超声剪切波的方法使用声辐射力来“推” 组织并产生剪切波。基于超声的方法用于检测剪切的传播 通过组织波浪。剪切波的传播速度可以通过几个参数来修改 包括组织中的弹性，粘弹性和非线性的机械性能。我们将使用剪切波 使用飞行时间方法测量肾脏中弹性特性的弹性图（SWE）。粘弹性 将通过将剪切波速度分散拟合到基于模型的方法来测量属性 流变模型或无模型方法，涉及提取剪切波速度的测量 和衰减以各种频率。最后，我们将使用一种称为Acousticticoalasticity的方法，该方法结合了 肾脏同种异体移植和SWE测量的压缩以估计从中估算非线性弹性模量 剪切模量数据以各种施加的应力获得。从这些参数提取的参数 将测量与结构（活检）和肾脏健康的功能度量进行比较（血清 肌酐，估计的肾小球过滤率和多普勒超声结果），以阐明分配方式 疾病改变了这些参数。建立这些关系将为 将这些弹性测量方法转发，以进行宽度临床用途，以评估 肾同种异体移植。 SWE测量的无创性，可在许多临床超声波上获得 扫描仪，使它们成为减少活检数量的工具，并用于 经常对患者对治疗的反应进行定量评估和监测，这将导致 降低医疗保健成本，并有可能改善患者的预后。为了实现这些目标，我们 建议以下特定目标。目的：1）评估SWE的使用来测量弹性机械 肾脏同种异体移植物结构和功能变化无创的特性。 2）评估 使用SWE测量粘弹性机械性能评估肾脏同种异体纤维化，炎症， 和功能。 3）评估使用声弹性来测量非线性弹性机械性能 评估肾脏外观的病理和功能变化。