Plane wave fast color flow mode imaging: a parameter study

A new Plane wave fast color flow imaging method (PWM) has been investigated, and performance evaluation of the PWM based on experimental measurements has been made. The results show that it is possible to obtain a CFM image using only 8 echo-pulse emissions for beam to flow angles between 45o. and 75o. Compared to the conventional ultrasound imaging the frame rate is ~ 30-60 times higher. The bias, Best of the velocity profile estimate, based on 8 pulse-echo emissions, is between 3.3 % and 6.1 % for beam to flow angles between 45o. and 75o, and the standard deviation, σest of the velocity profile estimate is around 2 % for beam to flow angles between 45o. and 75o. relative to the peak velocity, when the flow angle is known in advance. A study is performed to investigate how different parameters influence the blood velocity estimation. The results confirmed expectations for beam to flow angles between 45o. and 75o. The parameter study shows that the PWM using Directional velocity estimation gives the best results using spatial sampling interval ≤λ/10, correlation range ≥10λ, and number of directional signals ≥6. It is hereby shown that, by carefully choosing the set of parameters, PWM is feasible for fast CFM imaging with an acceptable bias and standard deviation.

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