MECHANICAL ORGINS OF SHOCK INDUCED BIOEFFECTS IN SHOCK WAVE LITHOTRIPSY

冲击波碎石术中冲击引起的生物效应的机械根源

• 批准号: 6316611
• 负责人: BRADFORD STURTEVANT
• 金额: $ 16.12万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-03-01 至 2001-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6316611
• 关键词: bioengineering /biomedical engineering; biomechanics; biomedical equipment development; cellular pathology; clinical biomedical equipment; iatrogenic disease; kidney disorder; kidney function; lithotripsy; mathematical model; mechanical pressure; mechanical stress; model design /development; nephrolithiasis; phantom model; tissue /cell culture; ultrasound biological effect

This grant is the continuation of a collaborative multi-disciplinary study of the mechanical initiation of injury to soft tissue in the kidney and of damage to tissue analogs by ESWL shock waves. Experiments are carried out in a laboratory lithotripter of our own design that mimics the Dornier HM3 electrohydraulic lithotripter. Finite-difference numerical solutions of the Euler equations are obtained for focusing shock waves interacting with tissue and kidney stones. Cooperative research is carried out with the other Projects of this Program Project Grant to advance the objectives of the Grant. The aims of this Project are: I. Extend the dose criterion developed in our previous work on the cavitation-free failure of planar membranes to more complex weak mechanical structures and, in collaboration with Project 2, to in vitro cell cultures. Included in this aim is the development of a tissue phantom which reliably mimics the shock-wave scattering properties of soft tissue, development PVDF transducer arrays, investigation of membrane material/cavitation-free host fluid combinations and thin-membrane cylindrical structures for damage studies, and collaborations with Projects 1 and 2 to develop a physically-based quantitative definition of ESWL dose. II. Initiate a new effort in Project 4 to demonstrate the mechanisms of kidney stone comminution by ESWL. Included in this aim is utilization of the Hopkinson bar technique to characterize the failure dynamics of real and phantom calculi, and development of a stone phantom which faithfully mimics the failure models of kidney stones. III. Develop numerical methods for solving the exact Euler equations of motion. Included in this aim is adaptation of the Amrita problem-solving environment to shock wave focusing problems, calculation of shock wave focusing by an ellipse in uniform and non-uniform media, and calculation of wave shapes and compressive stresses induced by impingement of a shock wave on a theoretical calculus. The hypothesis that the above aims are designed to test include: 1. A quantitative definition of ESWL dose, based on the physical properties of waves and tissue, can be developed to quantify the mechanical input of ESWL to tissue. 2. Comminution of kidney stones in ESWL occurs under shock compression by dynamic fatigue. 3. Accurate numerical calculations of shock pressure and wave geometry during shock wave focusing can be used with experimental data to elucidate mechanisms of stone comminution and tissue injury.

这项补助金是一项多学科合作研究的继续 对肾脏软组织的机械性损伤， ESWL冲击波对组织类似物的损伤。进行了实验 在我们自己设计的模仿Dornier HM 3的实验室碎石机中， 电液碎石机问题的三阶差分数值解 得到了聚焦激波与激波相互作用的欧拉方程， 组织和肾结石合作研究是与 本计划的其他项目项目补助金，以促进目标的 格兰特。该项目的目标是： I. 扩展了我们在以前的工作中开发的剂量标准， 平面膜对更复杂弱 机械结构，并与项目2合作，在体外 细胞培养这一目标包括开发一种组织模型 其可靠地模拟了软组织的冲击波散射特性， PVDF换能器阵列的研制，膜的研究 材料/无空穴的主体流体组合和薄膜 圆柱形结构的损害研究，并与合作 项目1和项目2，制定基于物理的 ESWL剂量。 二. 在项目4中启动一项新的工作，以展示 ESWL粉碎肾结石。这一目标包括利用 霍普金森杆技术表征真实的材料的失效动力学 和幻影结石，并发展一个石头幻影， 模仿肾结石的衰竭模型。 三.发展数值方法求解精确的欧拉方程 议案包括在这个目标是适应阿姆里塔解决问题， 环境对冲击波聚焦问题，冲击波计算 均匀和非均匀介质中的椭圆聚焦及其计算 冲击波冲击引起的波形和压应力 在理论演算上波动。 上述目标旨在检验的假设包括： 1.体外冲击波碎石剂量的定量定义，基于物理 波和组织的性质，可以开发来量化 ESWL对组织的机械输入。 2. ESWL中肾结石的粉碎发生在冲击压缩下， 动态疲劳 3.激波压力和波几何形状的精确数值计算 在冲击波聚焦过程中， 结石粉碎和组织损伤的机制。