Imaging of blood flow by NMR using phase velocity mapping

Preliminary results concerning the feasibility of using nuclear magnetic resonance (NMR) imaging techniques to visualize 3-D time-dependent flow fields are presented. The possibility of clinical application of this technique is evaluated by measuring steady flow in straight circular tubes, converging sections, and downstream of prosthetic aortic valves, as well as pulsatile flow in circular tubes. Measurements by NMR are compared with previously published results and theoretical data using different visualization techniques. The strategies and techniques used to display the flow images optimally are presented. Preliminary results on the accuracy of flow images obtained from NMR data are presented