Automatic Doppler angle and flow velocity measurement method

Current Doppler flow velocity measurements require the operator to manually set the direction of the flow velocity vector along the blood vessel axis on the 2D ultrasound scan image to determine the Doppler angle, and then to estimate the real flow velocity. In this article, we present an automatic flow velocity and Doppler angle measurement method, which exploits the symmetric focusing property of annular array transducers to enable the measurement of the flow in any three-dimension direction. The method uses the information of f_d (energy peak frequency) and f_max (maximum frequency) to obtain an automatic and direct estimation of flow velocity and Doppler angle. Successful measurements in phantom and on human subjects are presented in this paper.