Renal time-resolved MR angiography: Quantitative comparison of gadobenate dimeglumine and gadopentetate dimeglumine with different doses

PURPOSE: Results with different doses of gadobenate dimeglumine and gadopen tetate dimeglumine were compared at magnetic resonance (MR) angiography of the renal arteries. The signal-to-noise ratio (SNR) was evaluated as a quan titative measure of image quality. MATERIALS AND METHODS: Sixty consecutive patients (age range, 24-81 years; mean age, 65 years) underwent intraarterial digital subtraction angiography (DSA) and contrast material-enhanced time-resolved MR angiography. DSA was the standard of reference. Fifteen patients received gadopentetate dimeglu mine at doses of 0.2 or 0.1 mmol per kilogram of body weight. Fifteen patie nts received gadobenate dimeglumine at doses of 0.05 or 0.1 mmol/kg. The SN R was calculated in the aorta and both main renal arteries. The number and degree of stenoses of the renal arteries and accessory vessels were evaluat ed by four observers. RESULTS: SNRs with gadobenate dimeglumine at a dose of 0.1 mmol/kg were sig nificantly superior to those with gadopentetate dimeglumine at a dose of 0. 1 mmol/kg. Differences were not statistically significant between the SN Rs in the other groups. Eleven (85%) of 13 hemodynamically significant renal artery stenoses were detected correctly with MR angiography as were 22 (85% ) of 26 accessory renal arteries. CONCLUSION: SNRs with gadobenate dimeglumine were higher than those with ga dopentetate dimeglumine, but in most cases the differences in SNRs were not statistically significant.