Portal vein flow and motion quantification by Real-Time Phase Contrast MRI

Motivation: Portal vein flow is a crucial parameter to diagnose liver pathologies but poorly investigated by cardiac gated Phase Contrast MRIs due to breathing movement. Goal(s): Quantify portal vein flow by Real-Time-PCMRI under free breathing. Approach: Real-Time-PCMRI produced continuously (every 103 ms) velocities maps of the portal vein flow of 6 volunteers. We developed a post processing to automatically segment all the vessel area and calculate the blood flow dynamic key parameters. Results: The mean flow was 964±125 ml/mn. The mean area was 116±24 mm. The displacement of the area was 10±4 mm2. Free breathing significantly modulated the portal vein flow. Impact: Real-Time-PCMRI is a simple, rapid, non-invasive and unsynchronized imaging method to investigate liver vascularization to establish accurate quantitative physiological reference values. Dedicated post processing software should help to use it easily in clinic to better diagnosis and understanding liver pathologies.