A Low-cost, Intravascular Ultrasound Transducer System for Measuring Blood Flow

描述(申请人提供)：在美国，每年有超过一百万例微创手术--血管成形术、支架置入术、血栓摘除术--来保存血液流动。这个项目的目标是提供在这些过程中和之后测量这些血管中的血流的方法，这是现在不可能实现的。我们开发了一种新的血流测量组件，可以集成到微创介入设备中。在手术过程中，它向操作员提供成功恢复血流的定量反馈；手术后，它可以保留为留置导联，用于术后测量血流。它的低功耗要求也使其适合长期植入使用--一个小型植入装置，如起搏器，可以监测血流，并在血流下降需要干预时无线发送警报。这种血管内血流测量装置是一种新开发的独特的超声换能器系统。该设计利用了衍射光栅传感器的原理，已被证明可以准确地测量血液流量。为了使换能器适合血管内使用，已经发明了一种特殊的配置：这种换能器上的电极缠绕在一根杆子上，呈螺旋状，就像螺丝一样。这种设计有几个优点：它允许在高频下使用压电塑料，从而导致低功耗要求；使用压电塑料使轻巧、灵活的设备成为可能；它易于连接；重要的是，它的制造成本不高。该项目的第一阶段是通过制造这些换能器并在测试模体中展示它们的能力来验证这一概念，然后通过微创方法将一个放置在活动物身上，并展示成功的血流测量。公共卫生相关性：该项目的目标是开发一种血管内设备，用于测量手术期间和术后的血流量，以改善或恢复血流量。通过监测血液流动并提醒照顾者注意问题，它可以防止血液流动太少的严重后果。

DESCRIPTION (provided by applicant): Over a million minimally invasive procedures to preserve blood flow - angioplasties, stent placements, thrombectomies - are performed each year in the United States. The goal of this program is to provide means of measuring blood flow in these vessels during and after these procedures, something now not possible. We have developed a new blood-flow measuring component that can be integrated into minimally invasive interventional devices. During the procedure, it provides quantitative feedback to the operator on success in restoring blood flow; after the procedure, it can be remain as an indwelling lead to measure blood flow post-operatively. Its low power requirement also makes it suitable for long-term implantable use -- a small implanted unit, like a pacemaker, can monitor flow and wirelessly communicate an alert when declining blood flow demands intervention. This intravascular blood-flow measuring device is a newly developed, unique ultrasound transducer system. The design utilizes the principle of diffraction-grating transducers, which have been proven to measure blood flow accurately. A special configuration has been invented to make the transducer suitable for intravascular use: the electrodes on this transducer are wound around a rod, in helices, like a screw thread. This design has several advantages: it allows piezoplastics to be used at high frequencies, leading to low power requirements; use of piezoplastics makes a light, flexible device possible; it is easy to connect to; and, importantly, it is inexpensive to fabricate. Phase I of this project is to prove the concept by fabricating these transducers and demonstrating their capabilities in test phantoms, followed by placing one by minimally invasive means in a living animal and demonstrating successful blood flow measurement. PUBLIC HEALTH RELEVANCE: The goal of this program is to develop an intravascular device to measure blood flow during and after operations that improve or restore blood flow. By monitoring blood flow and alerting caregivers to a problem, it can prevent the serious consequences of too little flow of blood.