OBJECTIVETo evaluate the safety, tolerance and efficacy of Gd-BOPTA and Gd-DTPA in contrast-enhanced MR imaging of the liver.

METHODSForty-two patients having been suspected of suffering from primary liver tumor or hepatic metastasis by ultrasonography (US) or CT received Gd-BOPTA or Gd-DTPA in contrast-enhanced MRI examination pre- and post-contrast MRI. T(1)- and T(2)-weighted spin-echo, and T(1)-weighted gradient-echo images were acquired before injection. Dynamic T(1)-weighted gradient-echo images were obtained at 15 - 45 s, 1 - 2, 2 - 3, 4 - 5 and 8 min, respectively, after intravenous injection of Gd-BOPTA or Gd-DTPA at the same dose of 0.1 mmol/kg, and delayed T(1)-weighted spin-echo and gradient-echo images were acquired at 40 - 120 minutes after injection. All the images were assessed in three matched pairs including pre-contrast images vs. early post-contrast images; pre-contrast images vs. delayed post-contrast images; and pre-contrast images vs. early and delayed post-contrast images. The assessment was made in terms of 4 aspects including improved conspicuousness and/or delineation of liver lesions, improved confidence in lesion detection or exclusion, improved assessment of lesion internal morphology, and improved confidence in lesion characterization. The results of assessments were statistically compared inside every group or between two groups, and the radiological utility of contrast enhancement was also evaluated at the end of the study.

RESULTS1. There were significant differences between pre-contrast images vs. early post-contrast images and pre-contrast images vs. delayed post-contrast images inside the Gd-DTPA group, and the early post-contrast images were superior to delayed images. 2. There were significant differences between the two groups in terms of pre-contrast images vs. delayed post-contrast images, and Gd-BOPTA was superior to Gd-DTPA. 3. The quality of post-contrast images were improved obviously with a rate of 72.7% for Gd-BOPTA and 70.0% for Gd-DTPA, respectively, but without significant difference.

CONCLUSIONThe early post-contrast phase of Gd-DTPA-enhanced MR imaging is superior to delayed phase. The effects of Gd-BOPTA and Gd-DTPA in early post-contrast imaging are comparable, but Gd-BOPTA is significantly superior to Gd-DTPA in delayed post-contrast imaging.