2 PROTOTYPE BLOOD-POOL AGENTS FOR CONTRAST-ENHANCED MAGNETIC-RESONANCE ANGIOGRAPHY OF THE PORTAL-VEIN IN PIGS

Rationale and Objectives. Macromolecular ''bloodpool'' agents such as polylysine-gadopentetate dimeglumine or albumin-gadopentetate dimeglum ine, which provide prolonged intravascular enhancement, were tested as magnetic resonance (MR) angiography contrast agents for the portal ve in in pigs. Methods. Phase-contrast MR angiography of the portal veins was performed on six pigs before and after intravenous administration of polylysine-gadopentetate dimeglumine (n = 3) or albumin-gadopentet ate dimeglumine (n = 3). Results. The contrast-to-noise ratio of the p ortal veins was improved by 74% and 52%, respectively, using polylysin e-gadopentetate dimeglumine or albumin-gadopentetate dimeglumine. More branches of the intrahepatic portal veins were visualized on postcont rast images. Conclusion. Blood-pool paramagnetic contrast agents impro ved the visualization of hepatic vasculature using phase-contrast MR a ngiography in our experimental model.