基于光学相干检测的非接触式光声多普勒流速仪

Noncontact Photoacoustic Doppler Flowmetry Based on Optical Coherent Detection

在临床应用中,许多患处血液流速的测量都需要在无菌操作下进行。而传统的基于超声换能器实现的光声流速测量方式都需要在检测区域与探头之间填充超声耦合介质,从而无法实现无菌操作,限制了这种检测方式在临床上的应用。本文报道了一种非接触式光声多普勒流速仪,利用低相干的麦克尔逊干涉仪探测光声信号实现了流速测量。与超声探头为探测装置的光声多普勒血流仪相比,该方法可以实现非接触式的光声流速测量。在模拟血液样品实验中,定量的测量了横向流速,其速度范围在0. 2-3 mm/s,同时获得了截面流速图像。另外,活体小鼠耳部流速图像证明了该方法可以非接触、定量的测量血流信息。

In clinical applications,the measurement of blood flow velocity in many affected areas needs to be performed under aseptic conditions. However,the traditional photoacoustic flow measurement methods based on ultrasonic transducers,the ultrasonic coupling medium between the probe and the detection area need to be filled,and thus sterile operation cannot be achieved,which could restrict clinical application. In this paper,a non-contact photoacoustic Doppler flowmetry is reported,and a low coherent Michelson interferometer is used to detect the photoacoustic signal to realize the velocity measurement. Compared with the photoacoustic Doppler flowmetry using the ultrasonic probe,this method can realize noncontact photoacoustic flow measurement. The transverse flow ranging from 0. 2-3 mm/s as well as sectional flow imaging could be quantitatively measured measurement in the blood-mimicking flow phantoms. Besides,the blood flow imaging of the mouse ear in vivo show that this method can quantitatively measure blood flow information in a noncontact fashion.