REAL-TIME 3-DIMENSIONAL VELOCITY VECTOR MEASUREMENT USING THE WEIGHTED PHASE GRADIENT-METHOD

Although the technique for measuring blood flow based on the ultrasoni c Doppler method is an important means for clinical diagnosis, it is i nappropriate for quantitative assessment of blood flow since the true three-dimensional (3-D) velocity component cannot be obtained in many cases. In this paper, to overcome the restriction, a new method of 3-D velocity vector measurement is proposed. By detecting the gradient of the weighted phase shift distribution un the receiving aperture, the proposed method enables us to employ a smaller single aperture compare d with those used in conventional techniques, and its sensitivity is i ndependent of the direction of transverse flow. Furthermore, real-time measurement can be realized since the autocorrelation technique is ut ilized for the phase shift extraction as well as the present Doppler m ethod. The basic performance of the method is evaluated by computer si mulation. Moreover, sector scan imaging is constructed by the proposed method and compared with the conventional method. The obtained result s validated the feasibility and ability of the proposed method for mea suring 3-D velocity.