Gadolinium Ethoxybenzyl Diethylene-triamine-pentaacetic-acid-enhanced Magnetic Resonance Imaging Perfusion and Multiple Hepatobiliary-phase Imaging for Quantitative Assessment of Liver Fibrosis in Rat Models / 中国医学科学院学报

ABSTRACT

Objective To investigate the value of gadolinium ethoxybenzyl diethylene-triamine-pentaacetic-acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) in detecting different stages of liver fibrosis in rats.Methods Rat models of liver fibrosis were induced by carbon tetrachloride intraperitoneal injection for 4 - 12 weeks (n=45). The control group was applied with 0.9% saline (n=15). The MRI protocol contained both dynamic contrast-enhanced sequence (60 continuous scans within 3 minutes,including three pre-contrast measurements) and multiple hepatobiliary-phase acquisitions (every 5 minutes after contrast injection,60 minutes in total). METAVIR score was used to grade liver fibrosisnormal (F0),mild fibrosis (F1 - F2),and advanced fibrosis (F3 - F4). Liver perfusion parameters [transfer constant (K ),extravascular extracellular volume fraction (V),initial area under curve (iAUC),maximum relative enhancement (RE),and time of maximum RE (T)] as well as hepatobiliary-phase parameters [RE at different time point,the decrease of RE (RE=RE - RE),and elimination half-life of RE (T)] were measured and compared with ANOVA analysis and Spearman rank correlation.Results Thirty-one rats completed MRI exams and were then divided into normal (n=10),mild fibrosis (n=10),and advanced fibrosis (n=11) groups. K ,V and iAUC decreased as liver fibrosis progressed (r=-0.631,P=0.002;r=-0.503,P=0.017;r=-0.446,P=0.037). K and V showed significant differences among three groups(F=7.011,P=0.005;F=4.656,P=0.023). K and V were significantly lower in advanced fibrosis group than in normal group (P=0.001,P=0.009). There were statistical significant differences of T,T and RE among groups(F=6.633,P=0.005;F=5.493,P=0.010;F=5.343,P=0.014). Compared to normal and mild fibrosis groups,advanced fibrosis group had significantly longer T and T (P=0.005,P=0.004;P=0.008,P=0.008)and significantly lower RE(P=0.007,P=0.012).Conclusion Perfusion and multi-hepatobiliary-phase parameters such as K ,V,T, T and RE obtained from Gd-EOB-DTPA-enhanced MRI,may be valuable for detecting and staging liver fibrosis.