Quarter-Dose (0.025 mmol/kg) Gadobenate Dimeglumine for Abdominal MRI in Patients at Risk for Nephrogenic Systemic Fibrosis: Preliminary Observations

Abstract

The purpose of this study is to evaluate the feasibility of 0.025 mmol/kg gadobenate dimeglumine, which is one quarter of the standard dose, for abdominal 3-T MRI studies in patients considered to be at risk for nephrogenic systemic fibrosis, using qualitative and quantitative measures and comparison with higher doses. The MRI database was retrospectively searched to select consecutive patients who underwent quarter-dose gadobenate dimeglumine-enhanced abdominal MRI at 3 T, between January 1, 2009, and January 15, 2010, and who underwent half-dose (0.05 mmol/kg) gadobenate dimeglumine-enhanced abdominal MRI at 3 T during one randomly chosen month. There were 25 patients in the final quarter-dose group (16 men and nine women; mean age, 57 years) and 44 patients in the half-dose group (21 men and 23 women; mean age, 58 years). The enhancement of abdominal organs and aorta was evaluated qualitatively and quantitatively on contrast-enhanced images. The overall quality of abdominal enhancement was also evaluated. Reviewers rated the diagnostic enhancement of the evaluated organs in all phases of enhancement for both studied doses, but the half dose had significantly higher ratings than did the quarter dose in all comparisons (p, 0.034 to < 0.0001), except in the pancreas in the early hepatic venous phase (p = 0.095 for reviewer 1; p = 0.0611 for reviewer 2). The overall enhancement quality of the quarter dose was rated as good in all phases of enhancement, although it was significantly lower than that for the half dose (p ≤ 0.0001). The liver, pancreas, renal cortex, and aorta had 1.52-1.93-fold, 1.53-1.90-fold, 1.46-1.77-fold, and 1.58-1.84-fold, respectively, higher percentages of enhancement with the half dose than with the quarter dose (p, 0.0049 to < 0.0001). A one-quarter dose of gadobenate dimeglumine at 3 T is a feasible alternative for abdominal MRI in patients at risk for nephrogenic systemic fibrosis. Our results might have important clinical implications, because greater safety may be conferred on patients with poor renal function with this low dose of contrast agent.