Phase-control MR angiography of the portal vein

Phase-contrast MR angiography was used to image the portal vein in three normal volunteers. Between one and three breath-holding images with flow sensitivities in orthogonal directions were acquired and summed. The velocity-sensitive gradients were optimized for the range of expected velocities as well as for suppression of signal from overlapping arterial structures. Spatial presaturation was used superior to the imaging slab. With a single horizontal flow-sensitive direction, the main portal vein, right portal vein, and splenic veins were seen in all cases. With additional flow-sensitive directions, the left portal vein and the superior mesenteric vein were visualized