Figure 1
From: High-speed, high-frequency ultrasound, in utero vector-flow imaging of mouse embryos

Vector-flow map of a 1-cm diameter scattering phantom rotating counter-clockwise with a maximum expected velocity of 3.1 cm/s at the outer edge of the phantom. The vector-flow map indicates the direction of rotation with a velocity gradient from the maximum velocity at the outer edge to zero in the center of the phantom. Unlike when using traditional Doppler, lateral flow components could be resolved.