Rapid assessment of vascular grafts patency

描述（由申请人提供）：本项目的长期目标是引入“智能听诊器”技术，使用血管声音的计算机分析立即、准确、安全、轻松且廉价地检测血管受损。本项目的具体目标是开发一种用于监测血管旁路移植物、肾血液透析通路移植物和瘘管的器械。最终产品不仅可以检测狭窄的存在，还可以检测其严重程度。该设备的优点包括：高准确性、非侵入性、低成本、易于使用、最小的培训要求和立即的结果。第一阶段的工作重点是肾透析通路移植物和瘘，并且在检测血管口径的微小变化（<20%）方面显示出较高的准确性（p <0.0001），与介入放射学相比，相关系数为0.92。我们的第一阶段数据还表明，一些工程修改可能会提高设备性能，并导致一个更临床有用的工具。在第二阶段，我们将测试和实施具体的工程修改，并制造原型用于血管旁路移植物和肾血液透析移植物或瘘的临床研究。研究结果将包括与超声稀释和双功超声竞争技术相比的准确性、易用性、培训要求、成本和患者接受度的评价。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。考虑到有旁路移植物、血液透析移植物或瘘管的个体数量，我们的仪器的潜在市场很大。

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.