Digital thermal monitoring (DTM) of vascular reactivity closely correlates with Doppler flow velocity.
Digital thermal monitoring (DTM) of vascular reactivity closely correlates with Doppler flow velocity.
复制标题
DOI：
10.1109/iembs.2009.5333962
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Hartley CJ
中科院分区：
文献类型：
--
作者：
McQuilkin GL;Panthagani D;Metcalfe RW;Hassan H;Yen AA;Naghavi M;Hartley CJ
外周血管反应性的无创性测量作为血管功能的指标，为心血管高危人群的筛查提供了有价值的工具。出于实用和经济的考虑，这种测试必须成本低、使用简单。为此，用数字温度监测(DTM)取代通常用于该测量的更昂贵和更复杂的多普勒系统是有利的。建立了一个信号处理模型，以建立手指温度反应性和血流反应性之间的关系的基础，在一过性臂动脉阻断和再灌注方案(反应性充血)后。通过8 MHz的多普勒探头从受试者的桡动脉采集血流速度信号，同时通过DTM传感器从指端采集同步的DTM信号。该模型通过采用指数脉冲函数的反卷积方法将DTM温度信号转换为归一化流量信号。将DTM归一化血流信号与多普勒传感器计算的同步低频归一化血流信号进行比较。来自DTM和多普勒传感器的归一化血流信号被发现在再灌注期间产生类似的反应性反应。从DTM和多普勒传感器获得的反映充血容量的反应面积被发现在±15%以内。总之，该信号处理模型提供了一种使用DTM传感器测量血管反应性的方法，这与由更复杂的多普勒系统获得的结果相当。
The noninvasive measurement of peripheral vascular reactivity, as an indicator of vascular function, provides a valuable tool for cardiovascular screening of at-risk populations. Practical and economical considerations demand that such a test be low-cost and simple to use. To this end, it is advantageous to substitute digital thermal monitoring (DTM) for the more costly and complex Doppler system commonly used for this measurement. A signal processing model was developed to establish the basis for the relationship between finger temperature reactivity and blood flow reactivity following a transient brachial artery occlusion and reperfusion protocol (reactive hyperemia). Flow velocity signals were acquired from the radial artery of human subjects via an 8 MHz Doppler probe while simultaneous DTM signals were acquired from a distal fingertip via DTM sensors. The model transforms the DTM temperature signals into normalized flow signals via a deconvolution method which employs an exponential impulse function. The DTM normalized flow signals were compared to simultaneous, low-frequency, normalized flow signals computed from Doppler sensors. The normalized flow signals, derived from DTM and Doppler sensors, were found to yield similar reactivity responses during reperfusion. The reactivity areas derived from DTM and Doppler sensors, indicative of hyperemic volumes, were found to be within ± 15%. In conclusion, this signal processing model provides a means to measure vascular reactivity using DTM sensors, that is equivalent to that obtained by more complex Doppler systems.