Relationship between severity of liver dysfunction and the relative ratio of liver to aortic enhancement (RE) on MRI using hepatocyte-specific contrast.

Abstract

PURPOSE: To evaluate differences in liver enhancement among patients with low and

high morbidity risks and to determine the relationship between severity of liver

dysfunction and the relative ratio of liver to aortic enhancement (RE) on MRI

using hepatocyte-specific contrast. MATERIALS AND METHODS: A total of 126

patients underwent magnetic resonance imaging (MRI) and blood serum testing

including serology, bilirubin, international normalized ratio, and creatinine

tests. Radiologists analyzed a region of interest in the liver and aorta on

precontrast and 10- and 20-minute delayed hepatobiliary phase MR images. Liver

enhancement after 10 (LE10min ) and 20 minutes (LE20min ) were compared between

the low- and high-risk groups by independent t-test. Regression analysis was used

to assess the relationship between the Model for Endstage Liver Disease (MELD)

score and RE. RESULTS: All 126 patients were classified into either the low-risk

group (MELD <8; n = 85) or high-risk group (MELD >/=8; n = 41). The mean LE10min

and LE20min were significantly higher in the low-risk group (471.61; 95%

confidence interval [CI]: 449.79-493.43 and 510.69; 95% CI: 486.51-534.87,

respectively) than in the high-risk group (401.6776; 95% CI: 364.75-438.61 and

413.81; 95% CI: 370.91-456.70). There was a moderate inverse correlation between

MELD score and the relative ratio of liver enhancement (RLE) (r = -0.5442; 95%

CI: -0.6480 to -0.4207; P<0.01), but a high positive correlation between MELD

score and RE (r = 0.7470; 95% CI: 0.6665-0.8102; P < 0.01). CONCLUSION: Although

liver enhancement was significantly greater in low-risk patients compared to

high-risk patients, RE may be a better predictor of liver function than RLE.