Potential of Gd-EOB-DTPA-enhanced MR imaging for evaluation of bile duct ligation-induced liver injury in rabbits

The aim of this study was to evaluate the potential of gadoxetic acid (Gd-EOB-DTPA)-enhanced MRI for assessment of bile duct ligation (BDL)-induced chelostatic liver injury in an animal model by T-1 relaxation time measurements and first-pass perfusion analyses. Twenty-four rabbits were classified into three groups as follows: control group (N group), n = 8; BDL group studied on the 5th postoperative day (BDL-5d group), n = 8; BDL group studied on the 14th postoperative day (BDL-14d group), n = 8. A dual flip angle three-dimensional gradient echo sequence with volumetric interpolated breath-hold examination was performed before and at 20 min [hepatobiliary phase (HBP)] after Gd-EOB-DTPA administration. Besides, early dynamic contrast-enhanced MRI was performed for 4.32 min with a temporal resolution of 2.2 s. T-1 relaxation times of liver parenchyma were measured and perfusion parameters were calculated. Dilatation of intra-hepatic bile duct was found only in the BDL-14d group. HBP T-1 relaxation times of the BDL-5d and BDL-14d groups were significantly prolonged (p < 0.001) and the enhancement slope percentage of BDL-5d and BDL-14d groups were significantly lowered in comparison with that of the N group (p < 0.001). There were no differences between the BDL-5d group and the BDL-14d group for HBP T-1 relaxation times and the enhancement slope percentage (p > 0.05). Area under the receiver operating characteristic curve of HBP T-1 relaxation time and the enhancement slope percentage for the selection of chelostatic liver were 0.98 and 0.92 for the BDL-5d group, and 0.96 and 0.98 for the BDL-14d group, respectively. HBP T-1 relaxation time measurement in combination with first-pass enhancement slope percentage withhold promise to assess extrahepatic chelostatic liver injury.