Detecting Impending Dialysis Access Graft Failure

描述（由申请人提供）：本项目的目的是开发一种低成本、易于使用的仪器，用于测量人工透析通路移植物中的血流量。有了这样的仪器，这些移植物可以在足够频繁的时间间隔监测，以检测预测移植失败的下降流量水平。对于25万接受血液透析的美国人来说，这种移植失败是一个主要的医疗问题。 拟议的仪器将利用一种新的超声换能器，衍射光栅换能器，在一个特殊的多普勒技术，消除了需要在测量过程中成像的移植物，特别是由最低限度熟练的操作员适合。该仪器的早期版本已显示出在测量透析通路移植物流量方面的前景，并且已证明移植物流量的正常生理变化范围足够小，使得所提出的流量测量应揭示即将发生的移植物失效。 在本项目的拟定第一阶段，将构建所需仪器的原型，并通过在少量血液透析患者中与标准流量技术进行比较，在临床使用中验证其准确性和易用性。随着仪器的可行性得到证明，第二阶段将继续建造一些这样的仪器，用于多中心试验，以证明它们的使用可以延长人工透析移植物的寿命。 这种移植物寿命延长的经济效益每年可接近10亿美元，确保了该仪器的商业化。

DESCRIPTION (provided by applicant): The aim of this program is to develop a low-cost, easy-to-use instrument to measure the blood flow in artificial dialysis access grafts. With such an instrument, these grafts could be monitored at frequent enough intervals to detect the falling flow levels that predict graft failure. Such graft failure is a major medical problem for the 250,000 Americans who undergo hemodialysis. The proposed instrument will utilize a new kind of ultrasound transducer, the diffraction-grating transducer, in a special Doppler technique that eliminates the need for imaging the graft during measurement, and is especially suitable for by minimally skilled operators. An early version of this instrument has shown promise in measuring dialysis access graft flow, and has proven that the range of normal physiological variation in graft flow is small enough that the proposed flow measurements should reveal impending graft failure. In the Proposed Phase I of this project, a prototype of the desired instrument will be constructed and its accuracy and ease of use validated in clinical use by comparison with standard flow techniques in a small number of hemodialysis patients. With the feasibility of the instrument so demonstrated, Phase II would continue with construction of a number of such instruments to be used in a multi-center trial to prove that their use can extend the life of artificial dialysis grafts. The economic benefit of such graft life extension can approach a billion dollars a year, ensuringcommercialization of the instrument.