Plane-wave vector-flow imaging of adult mouse heart

High-frequency ultrasound Doppler modes have been used extensively for murine cardiovascular (CV) studies, but traditional linear-array imaging modes are limited in terms of spatial and temporal resolution. Plane-wave imaging methods allow for high-speed vector-flow information to be obtained throughout a full image frame. Plane-wave imaging has been demonstrated in human CV studies, but its use in mouse models has received minimal attention. A Verasonics Vantage with an 18-MHz linear array was used to acquire plane-wave data at a frame rate of 30 kHz from the left ventricle of adult mice. Batches of 3 transmissions spanning ± 5 degrees were sent out. The mouse was placed supine on a heated imaging platform and then 2D + time data sequences. The data were beamformed using standard delay-and-sum methods and vector-flow estimates were obtained at each pixel location using a least-squares, multi-angle Doppler analysis approach. Vortex patterns in the left ventricle were visualized over several heart cycles s...