In-vivo high dynamic range vector flow imaging

Current vector flow systems are limited in their detectable range of blood flow velocities. Previous work on phantoms has shown that the velocity range can be extended using synthetic aperture directional beamforming combined with an adaptive multi-lag approach. This paper presents a first in-vivo example with a high dynamic velocity range. Velocities with an order of magnitude apart are detected on the femoral artery of a 41 years old healthy individual. Three distinct heart cycles are captured during a 3 secs acquisition. The estimated vector velocities are compared against each other within the heart cycle. The relative standard deviation of the measured velocity magnitude between the three peak systoles was found to be 5.11% with a standard deviation on the detected angle of 1.06°. In the diastole, it was 1.46% and 6.18°, respectively. Results proves that the method is able to estimate flow in-vivo and provide quantitative results in a high dynamic velocity range. Providing velocity measurements during the whole cardiac cycle for both arteries and veins.