Improving 3D MR Velocity-Vector Field Mapping by Divergence-Free Image Reconstruction

Julia Busch^1,2, Daniel Giese^1,3, Lukas Wissmann¹, Sebastian Kozerke^1,3

The accuracy of velocity data derived from phase-contrast measurements is often compromised by partial volume effects and system imperfections. Although correction algorithms exist which aim to correct for noise and eddy-current related phase offsets residual phase errors remain. The present work introduces divergence-free image reconstruction for 3D phase-contrast vector field mapping based on a synergistic combination of normalized convolution and divergence-free radial basis functions. Using computer simulations and in-vivo data it is demonstrated that vector field divergence arising from measurement imperfections can be significantly reduced resulting in improved vector field representations.