Eisenoxydkontrastmittel verbessern die kernspintomographische Darstellung des portalvenosen Systems - Eine tierexperimentelle Untersuchung

Purpose: The aim was to demonstrate that intravenous superparamagnetic iron oxide contrast agents improve the delineation of the portal venous system. Material and methods: The portal venous system of 8 minipigs was demonstrated by a FLASH 2-D MRA-sequence. Scans were acquired before and after intravenous administration of 10 and 20 μmol/kg of a superparamagnetic iron oxide contrast agent (SHU 555 A). Signal intensities were measured in the portal vein and hepatic parenchym and contrast-to-noise ratios were calculated. Results: Following a cumulative dose of 10 μmol iron oxide, hepatic parenchymal signal intensity decreased to 67 ± 6%, following 20 μmol to 29 ± 4%, and following 40 μmol to 13 ± 2% of control (p < 0.0001). These effects improved the contrast-to-noise ratio of the portal vein (469 ± 114%, 858 ± 243%, and 957 ± 272% of control in the left portal vein main branch, p = 0.02). Conclusion: A decrease in hepatic parenchymal signal due to a magnetic susceptibility effect accounts for an improvement of portal venous conspicuity following intravenous administration of iron oxide contrast medium.