Tracking kidney stones during shock wave lithotripsy

描述（由申请人提供）：本申请涉及广泛的挑战领域（06）使能技术和特定的挑战主题，06-DK-104使能技术，用于预防和治疗NIDDK使命内的疾病。.特别是，它涉及本挑战主题1/更好的微创工具中提到的三个优先领域。泌尿外科手术，以尽量减少并发症2/改进碎石机，以尽量减少并发症。3/创建新的或改进的机械设计和控制算法冲击波碎石术（SWL）是一种非侵入性手术，通过该手术，使用聚焦冲击波将肾结石破碎成足够小以自然通过的碎片。在美国，靶向通常在治疗开始前使用X射线成像完成。典型的治疗使用在30分钟内递送的2000个冲击波的数量级，并且在这段时间内偶尔检查靶向。然而，由于呼吸（和其他患者运动），结石并不是在整个时间内都处于碎石机的焦点中，因此许多冲击波错过了结石。这些错误定向的冲击波导致对周围组织的创伤，而没有任何治疗益处。冲击波碎石术的创伤与急性和慢性并发症有关。我们建议开发一种实时跟踪系统，可以改装到临床碎石机和门的碎石机，使其发射冲击波只有当石头是目标。在结石已经永久性地从焦点区域移动的情况下，系统将向泌尿科医生发出信号，指示应该用常规成像重新评估对准。通过消除错误定位的冲击波，该系统将在不影响破碎效率的情况下降低创伤的可能性。目标1：优化跟踪算法我们有初步数据表明，我们可以在体外环境（人造结石和人造组织）中跟踪肾结石。该算法将得到改进，以跟踪多个碎片，然后将构建和测试一个原型系统，可以改装为临床碎石机。目标二：使用体内模型评估跟踪跟踪系统将部署在临床碎石机上，并用于跟踪猪模型中肾结石的运动。在第一步中，将评估系统在受控运动下跟踪结石的精度。在第二步中，该系统将用于两台不同的碎石机，以跟踪治疗期间的结石和门控SW输送，并评估门控对碎裂和组织损伤的影响。该项目的可交付成果将是原型结石跟踪系统，可以改装到临床碎石机上。将评估这种新工具的性能，特别是其减少肾组织创伤的能力，同时仍然能够破碎结石。在两年的项目结束时，我们将能够计划临床试验。 公共卫生回顾：冲击波碎石术（SWL）是一种通过冲击波破碎肾结石的常见非侵入性技术。在SWL期间，结石由于呼吸而移动，并且目前许多冲击波错过了结石并损伤周围组织。我们的目标是开发一种基于超声波的跟踪系统，该系统只允许碎石机在结石到达目标时发射冲击波，从而保护周围组织。

DESCRIPTION (provided by applicant): This application addresses broad Challenge Area (06) Enabling Technologies and specific Challenge Topic, 06-DK-104 Enabling technology for the prevention and treatment of diseases within the NIDDK mission. . In particular, it addresses the three priority areas mentioned in this challenge topic 1/ better tools for minimally invasive ... urologic surgeries, to minimize complications 2/ improvement of lithotripters to minimize complications. 3/ Creation of new or improved mechanical designs and control algorithms Shock wave lithotripsy (SWL) is a non-invasive procedure by which focused shock waves are used to fragment kidney stones into pieces that are small enough to be passed naturally. In the United States targeting is normally accomplished using X-ray imaging before treatment starts. A typical treatment uses on the order of 2000 shock waves delivered over a 30 minute period and targeting is checked occasionally during this time. However, due to respiration (and other patient movement) the stone is not in the focus of the lithotripter the entire time and therefore many shock waves miss the stone. These mis-targeted shock waves result in trauma to the surrounding tissue without any therapeutic benefit. The trauma induced by shock wave lithotripsy has been associated with both acute and chronic complications. We propose to develop a real-time tracking system that can be retro-fitted onto clinical lithotripters and gate the lithotripter so that it fires a shock wave only when the stone is on target. In the case where a stone has permanently moved from the focal region the system will signal to the urologist that alignment should be reassessed with conventional imaging. By eliminating the mis-targeted shock waves the system will reduce the potential for trauma without affecting the fragmentation efficiency. Aim 1: Optimize tracking algorithm We have preliminary data to show that we can track kidney stones in an in vitro environment (artificial stone and artificial tissue). The algorithm will be improved to track multiple fragments and then a prototype system that can be retro-fitted to a clinical lithotripter will be constructed and tested. Aim 2: Evaluate tracking using an in vivo model The tracking system will be deployed on a clinical lithotripter and used to track the motion of kidney stones in a pig model. In the first step the accuracy of the system to track a stone under controlled motion will be assessed. In the second step the system will be used on two different lithotripters to track a stone and gate SW delivery during treatment and assess the impact of gating on fragmentation and tissue injury. The deliverable from this project will be prototype stone tracking system that can be retro-fitted onto a clinical lithotripter. The performance of this new tool will have been assessed in particular its ability to reduce trauma to kidney tissue while still being able to fragment stones. At the end of the two year project we will be in a position to plan clinical trials. PUBLIC HEALTH REVEVANCE: Shock wave lithotripsy (SWL) is a common non-invasive technique for breaking up kidney stones by shock waves. During SWL the stone moves due to respiration and presently many shock waves miss the stone and damage the surrounding tissue. Our goal is to develop an ultrasound based tracking system which will only allow the lithotripter to fire a shock waves when the stone is on target and therefore spare the surrounding tissue.