Enhancement Effects of Hepatic Dynamic MR Imaging at 3.0 T and 1.5 T Using Gadoxetic Acid in a Phantom Study: Comparison with Gadopentetate Dimeglumine

To identify the optimum sequence at gadoxetic acid enhanced hepatic dynamic magnetic resonance imaging in the arterial phase, we studied phantoms that contained gadoxetic acid or gadopentetate dimeglumine diluted in human blood. We obtained magnetic resonance images at 3.0 T and 1.5 T with one vendor (Siemens) using 3D-gradient echo (GRE)-, 2D-fast low angle shot (FLASH)-, and turbo spin echo sequences. Contrast ratio was highest for 3D-GRE; at both 3.0 T and 1.5 T it was superior when the contrast agent was gadoxetic acid. With both gadoxetic acid and gadopentetate dimeglumine, contrast ratio peaked at around 5-and 2 mmol/L on 3D-GRE-and 2D-FLASH images, respectively. Compared with gadopentetate dimeglumine, at 3.0 T, the peak contrast ratio of gadoxetic acid was 14.1% better on 3D-GRE images and 14.0% better on 2D-FLASH images; at 1.5 T it was 16.4% better on 3D-GRE- and 5.7% better on 2D-FLASH images. With respect to the magnetic field strength, at 3.0 T the peak contrast ratio of gadoxetic acid was 6.0% better than at 1.5 T on 3D-GRE images and 49.5% better on 2D-FLASH images; it was 8.5% better on 3D-GRE- and 44.6% better on 2D-FLASH images than when the contrast agent was gadopentetate dimeglumine. Thus, gadoxetic acid yielded better enhancement on 3D-GRE images acquired at 3.0 T than at 1.5 T and enhancement was better than that obtained with gadopentetate dimeglumine at the same concentration. Magn Reson Med 66:213-218, 2011. (C) 2011 Wiley-Liss, Inc.