Feasibility study of blood velocity vector estimation using three types of transducer

Ultrasound color Doppler imaging has been a useful technique for obtaining vascular blood flow information. The conventional method, however, suffers from angle dependency when the blood flow is normal to the ultrasound beam direction so that it is difficult to visualize the blood flow. To overcome this angle dependency, various vector Doppler imaging methods with multiple transmit and receive sub-apertures have been proposed and showed an angle independent vessel flow information. However, most of them are evaluated on a linear array transducer. This paper evaluates a vector Doppler algorithm consisting of one transmit (TX) sub-aperture and two receive (RX) sub-apertures based on the convex and phased array transducer. Vessel flow velocity magnitudes and directions obtained by the vector Doppler using the convex and phased array show, for convex transducer mean direction error of 8.6843 degrees and 0.3860 m/s of mean velocity magnitude error and for phased array 16.1693 degrees and 0.0247 m/s mean errors respectively. These result indicate that convex and phased array also provide an reasonable vessel velocity magnitude and flow direction comparing to the vessel information of linear transducer which are errors of 2.9440 degrees and 0.1710 m/s respectively.