Mechanical Response of Biological Tissue to Shock Waves

冲击波碎石术（SWL）在2000年被引入时，彻底改变了肾结石的治疗。 80年代然而，该技术的后续发展在临床上几乎没有改善。 结果，如结石清除率。此外，有研究表明，与慢性 并发症，特别是新发高血压和糖尿病。在目前的 基金期间已经确定了冲击波可以减少急性组织的策略， 损害项目4的目标是研究组织损伤的基本机制，无论是对 肾脏，PPG已证实其程度并确定可能的慢性影响， 胰腺在目标1中，我们将扩展当前的数值模拟工具来预测 肾和胰腺的碎石机这一工具将被广泛用于为其他机构提供输入数据。 目标。在目标2中，将评估该小组提出的一个假设，即重复冲击的直接影响 可能会造成损伤数学模型的初步结果预测， 在实验中首次观察到损伤的内髓中将更为重要。在目标3中，我们将使用 我们先进的建模和仿真工具，以了解介导的因素，在空蚀引起的伤害。 组织中空化的实验证据是明确的，但其损害的机制 在最初的几百次冲击波中，它被抑制的原因尚不清楚。 目标4将应用在前3个目标中开发的工具来评估声损伤和随后的 胰腺组织损伤，以了解碎石术诱发糖尿病的风险。目标5是 PPG的数据表明，宽聚焦区碎石机可以抑制损伤， 同时提高结石破碎度。我们的目标将是了解的物理性质的 声场，其导致减少的组织损伤但具有有效的破碎。Aim 6利用数据 这表明许多冲击波没有击中结石，但它们仍然会影响组织。我们计划开发一个 一种可以跟踪结石位置和门电流碎石机的设备，以确保冲击波只被发射 当石头对准目标时通过减少偏离目标的冲击波的数量，将减少对组织的损伤。 降低项目4的总体目标是提供一种实施冲击波碎石术的策略 通过了解组织损伤的基本机制， 工艺和开发新技术，将减少冲击波的影响。

Shock wave lithotripsy (SWL) revolutionized the treatment of kidney stones when it was introduced in the 1980s. However, the subsequent development of the technology has shown little improvement in clinical outcomes, such as stone free rate. Further there have been studies indicating an association with chronic complications in particular new onset hypertension and diabetes mellitus. Progress within the current funding period has identified strategies by which shock waves can be delivered with reduced acute tissue damage. The goal of Project 4 is to investigate the fundamental mechanisms of tissue damage, both to the kidney, where the PPG has confirmed its extent and identified possible chronic implication, and in the pancreas. In Aim 1 we will extend a current numerical simulation tool to predict the acoustic insult of a lithotripter to the kidney and pancreas. This tool will be used extensively to provide input data for other aims. In Aim 2, will evaluate a hypothesis developed by this group that the direct effect of repeated shocks on the tissue might initiate injury. Preliminary results from a mathematical model predict that this damage will be more important in the inner medulla where injury is first observed experimentally. In Aim 3 we will use our advanced modeling and simulation tools to understand the mediating factors in cavitation induced injury. Experimental evidence of cavitation in tissue is unambiguous, but the mechanisms by which it damages tissue and the reasons why it appears suppressed during the first few hundred shock waves are unclear. Aim 4 will apply the tools developed in the previous 3 aims to assess the acoustic insult and subsequent tissue injury to the pancreas in order to gain insight into the risk of lithotripsy inducing diabetes. Aim 5 is motivated by data from the PPG that indicates that a broad focal zone lithotripter can suppress injury and at the same time improve stone fragmentation. The goal will be to understand the physical properties of the acoustic field which result in reduced tissue damage but with effective fragmentation. Aim 6 exploits data that shows many shock waves do not hit the stone but they will still impact tissue. We plan to develop a device that can track stone location and gate current lithotripters to ensure that shock waves are only fired when the stone is on target. By reducing the number of off-target shock waves the insult to the tissue will be reduced. The overarching goal of Project 4 is to provide a strategy for shock wave lithotripsy to be delivered with fewer side effects by a combination of understanding the fundamental mechanics of the tissue damage process and developing novel technologies which will reduce the shock wave impact.