Angle-Independent Blood Flow Velocity Measurement With Ultrasound Speckle Decorrelation Analysis

Precise measurement of the blood flow velocity in major arteries is important for the assessment of circulation dysfunction but challenging when using a one-dimensional (1D) ultrasound transducer array. Current available ultrasound velocimetry methods are susceptible to the probe-to-vessel angle and require the vessels to be well-aligned within the imaging plane of the 1D transducer array. In this study, a novel angle-independent velocimetry (VT-vUS) based on the ultrasound speckle decorrelation analysis of the ultrasound field signal is proposed to measure the blood flow velocity using a conventional 1D ultrasound transducer array. We first introduced the principle and evaluated this technique with numerical simulation and phantom experiments, which demonstrated that VT-vUS can accurately reconstruct the velocity magnitude of blood flow at arbitrary probe-to-vessel angles for different preset flow speeds (up to ~2.5 m/s). Further, we applied VT-vUS to measure the pulsatile flow of the radial artery and carotid artery in a healthy volunteer. Results show that the absolute velocity profiles obtained with VT-vUS at different probe-to-vessel angles have high consistency and agree well with the absolute speed obtained with the color Doppler-corrected velocimetry throughout the cardiac cycle. With the ability to alleviate the dependency on probe-to-vessel angle, VT-vUS has the potential for circulation-related disease screening in clinical practices.