Superparamagnetic iron oxide-enhanced liver MRI with SHU 555 A (RESOVIST): New protocol infusion to improve arterial...

To compare the arterial enhancement of hypervascular hepatic lesions by T1-weighted 3D-GRE (gradient-recalled echo) fat-sat sequence after slow (0.5 mL/sec) and fast (2 mL/sec) RESOVIST infusion.

We prospectively enrolled 71 patients with hypervascular hepatic lesions to undergo dynamic magnetic resonance imaging (MRI) examination with RESOVIST. A total of 92 benign and malignant lesions, 44 of which histologically confirmed, were examined. Three blinded and independent readers visually assessed the arterial enhancement using a score from 0 (none) to 3 (maximum), the latter score comparable to that achievable by MultiHance administration.

Out of the 92 hypervascular lesions, 41, 31, and 20 nodules were examined using the slow, fast, and both protocols, respectively. Relevant enhancement (scores 2-3) was found in 42% vs. 14.5% of cases for slow and fast protocols, respectively. Intraindividual comparison evaluation confirmed the better results obtained by slow than fast protocol (25% vs. 10%), with statistically relevant difference in distribution of scores (P=0.0004). The slow protocol showed values between 0 and 3 with an arithmetic mean of 1.1; the fast one, on the other hand, showed values between 0 and 2 with an arithmetic mean of 0.66.

Slow infusion improves arterial enhancement after RESOVIST administration.