MR-imaging features of hepatocellular carcinoma capsule appearance in cirrhotic liver: comparison of gadoxetic acid and gadobenate dimeglumine

Purpose: The purpose of the study is to compare the MR-imaging features of hepatocellular carcinoma (HCC) capsule appearance on gadoxetic acid and gadobenate dimeglumine-enhanced MR imaging, using imaging-based presumptive diagnosis of HCC as the reference standard. Methods: Gadoxetic acid and gadobenate dimeglumine-enhanced MR imaging of 51 patients with 71 HCCs were retrospectively reviewed. Three readers graded in consensus, using a five-point scale, the presence (score 4-5) of capsule appearance on images obtained during T1-weighted GRE portal venous phase (PVP), 3-min phase, and hepatobiliary phase (HBP). The Fisher's exact test and the t student unpaired test were performed. Results: A hyperintense capsule appearance was present either on PVP or 3-min phase in 11/46 and in 24/25 HCCs imaged with gadoxetic acid and gadobenate dimeglumine-enhanced MR imaging, respectively (24% vs. 96% p < 0.001). A hypointense capsule appearance was present on HBP in 8/46 and 0/22 HCCs evaluated with gadoxetic acid and gadobenate dimeglumine-enhanced MR imaging, respectively (17% vs. 0% p = 0.046). A capsule appearance was detected either on PVP, 3-min phase, or HBP in 17/46 (37%) HCCs after gadoxetic acid injection and in 24/25 (96%) HCCs after gadobenate dimeglumine injection (p < 0.001). Conclusions: A capsule appearance was more frequently seen on gadobenate dimeglumine-enhanced MR imaging when compared to gadoxetic acid-enhanced MR imaging.