Arterial Pressure Loss from Vascular Vector Flow Mapping with Conventional Color Doppler.

In the presence of a significant arterial stenosis, i.e. a constriction of the arterial lumen, a loss of pressure appears due to the turbulent mixing in the divergent region of the flow. We propose a non-invasive approach, by vascular color Doppler ultrasound, for the measurement of stenotic pressure loss. To this end, we retrieve 1) the transtenotic velocity vector field from conventional color Doppler data, using a constrained optimization method. We then estimate 2) the relative pressure field by combining the Bernoulli and Navier-Stokes equations. To validate this strategy, we developed an in silico pipeline including both fluid dynamics (CFD) and ultrasound imaging (SIMUS software) simulations. As a preliminary test, an in vitro acquisition (color Doppler vs. pressure wire) demonstrated the experimental feasibility of our new method. Our proof-of-concept results tend to demonstrate that it is possible to estimate the pressure losses in arterial stenoses by color Doppler ultrasound.