Gadolinium-enhanced arterial-phase MR imaging of hypervascular liver tumors: Comparison between tailored and fixed scanning delays in the same patients

The purpose of this study was to compare in the same patients tailored and fixed scanning delays during gadolinium-enhanced arterial-phase magnetic re sonance imaging of hypervascular liver tumors. Tailored scanning delays wer e obtained with automated region of interest threshold triggering, A delay of 23 seconds between the start of contrast material injection and imaging was used for fixed delay examinations. Quantitative and qualitative evaluat ion was performed in 21 patients with normal cardiac function referred for MR assessment of hypervascular liver tumors. In the tailored examinations, the median time delay between the start of contrast material injection and the start of magnetic resonance imaging was 21 seconds (range, 18-34 second s). The median tumor-to-liver contrast during tailored examinations was 19. 1 versus 14.7 during fixed delay examinations, This difference, however, wa s not significant. Similarly, the enhancement in the aorta, the portal vein , the liver, and the tumor did not differ significantly between examination s performed with tailored and fixed delays. It is concluded that in our gro up of patients with hypervascular liver tumors and normal cardiac function, no significant improvement in tumor-to-liver contrast and enhancement duri ng the arterial phase was found when gadolinium-enhanced magnetic resonance imaging was performed with a tailored scanning delay rather than with a fi xed delay. (C) 2000 Wiley-Liss, Inc.