眼部血流多普勒信号的检测研究

Research on Detection of Ophthalmic Blood Flow Doppler Signals

研制以超声波为载体的电路系统,探测眼部血流多普勒信号,并进行频谱分析。硬件设计包括:信号控制、超声波发射/接收、高频放大、正交检波以及距离选通等电路;将检测信号数字化后,进行数字信号处理并绘制频谱分析图。同时,构建物理仿真模型验证系统功能;对人体正常眼组织的检测,获得眼动脉中血流信号的频谱分析图。结果表明,系统有效实现了血流流速的检测、血流方向的辨别和距离选通等功能;对人体正常眼组织检测所获得的频谱分析图中三峰双切迹状明显,与正常人体眼动脉血流参数吻合。作为专用眼科超声多普勒诊断仪的前期探索性研究,本设计能够准确的提取被测血流的多普勒频移信号,具有很好的应用前景。

A set of circuits for detecting ophthalmic blood flow Doppler signals was developed and spectral analysis was realized as well.The hardware design included the circuits for signals control,ultrasound transmitting and receiving,high-frequency amplifying,quadrature detection,range gating and so on.The received signals were digitalized and processed,and spectral analysis for the signals was conducted.By building a physical simulation model,the functions of the system were validated.By detecting normal human eyes,the blood flow＇s spectral analysis of ophthalmic artery was gained.The results showed that the system could achieve the functions for detecting the velocity and direction of blood flow and range gating.The three peaks and two notches in spectral analysis were obvious and consistent with the blood parameters in ophthalmic artery.The design could get Doppler shift signals of detected blood flow accurately.This preliminary research on special device for ophthalmic ultrasonic Doppler diagnosis is promising for application.