Rapid assessment of vascular grafts patency

描述（由申请人提供）：该项目的长期目标是引入“智能听诊器”技术，通过对血管声音的计算机分析，立即，准确，安全，轻松和廉价地检测血管损伤。该项目的具体目标是开发一种监测血管旁路移植、肾血液透析通道移植和瘘管的设备。最终的产品将不仅检测狭窄的存在，而且其严重程度。该设备的优点包括：精度高、无侵入性、成本低、使用方便、培训要求低、效果立竿见影。I期研究的重点是肾透析通道移植物和瘘管，与介入放射学相比，在检测血管口径的微小变化（<20%）方面显示出很高的准确性（p < 0.0001），相关系数为0.92。我们的I期数据还表明，一些工程修改可能会提高设备的性能，并成为一种更有用的临床工具。在第二阶段，我们将测试和实施具体的工程修改，并制造用于血管旁路移植、肾血液透析移植或瘘管临床研究的原型。研究结果将包括准确性、易用性、培训要求、成本的评估，以及与超声稀释和双工超声等竞争技术相比的患者接受程度。这些研究将考虑FDA关于获得上市前批准的建议，我们将根据研究结果寻求FDA的PMA或510k批准。我们的仪器的潜在市场是巨大的，因为有大量的患者进行了旁路移植、血液透析移植或瘘管。

DESCRIPTION (provided by applicant): The long-term objective of this project is the introduction of "smart stethoscope" technology to immediately, accurately, safely, easily and inexpensively detect blood vessel compromise using computerized analysis of vascular sounds. The specific goal of this project is to develop a device for surveillance of vascular bypass grafts, and renal hemodialysis access grafts and fistulas. The final product will not only detect the presence of stenosis but also its degree of severity. Advantages of the device include: high accuracy, non- invasiveness, low cost, ease of use, minimal training requirements, and immediate results. The Phase I effort focused on renal dialysis access grafts and fistulas, and showed high accuracy (p <.0001), in the detection of even small changes (<20%) in vessel caliber with a correlation coefficient of 0.92 compared to interventional radiology. Our Phase I data also suggested that some engineering modifications will likely enhance the device performance and lead to an even more clinically useful tool. During Phase II, we will test and implement specific engineering modifications, and fabricate prototypes for use in clinical studies of vascular bypass grafts, and renal hemodialysis grafts or fistulas. Study outcomes will include evaluations of accuracy, ease of use, training requirements, cost, and patient acceptance compared to the competing technologies of ultrasound dilution, and duplex US. The studies will take into account FDA recommendations for obtaining premarket approval, and we will seek a PMA or 510k approval from the FDA based upon study results. The potential market for our instrument is large given the number of individuals with either bypass grafts, or hemodialysis grafts or fistulas.