Investigation of flows with complex geometry using coherence domain tomography

The experimental methods of Doppler OCT are applied for two-dimensional flow mapping of highly scattering fluid in a converging flow to demonstrate non-invasive methods of velocity distribution mapping before and after the entry to a lumen of smaller diameter. A flow with complex geometry is scanned with ~10x10x10 μm 3 spatial resolution. Velocity profiles of different shapes were obtained before and after the entry. Blunted, triangular and parabolic velocity profiles as well as structural images of the converging flow and images of a specific velocity are demonstrated. Broadening of Doppler spectra obtained with slow and rapid scanning optical delay lines are compared. Structural images of in vivo human finger blood vessels before and after optical clearing using rapid scanning optical delay line are presented.