Applied value of 3.0T blood oxygen level dependent (BOLD) MRI in the diagnosis of hepatic warm ischemia-reperfusion injury (WIRI) in rabbits

Abstract

Objective To investigate the applied value of 3.0T blood oxygen level dependent (BOLD) MRI in the diagnosis of hepatic warm ischemia-reperfusion injury (WIRI) in rabbits. Method Twenty healthy adult New Zealand white rabbits were randomly divided into two groups by using the stochastic indicator method. In 10 rabbits enrolled in the treatment group, the model of hepatic WIRI after ischemia for 30 min followed by 6-h reperfusion was established, and the remaining 10 rabbits were chosen as the normal control group and were not subjected to any surgery. All the experimental rabbits were scanned by 3.0T MRI and BOLD MRI. T2* values were separately measured by 2 considered radiologists and the R2* values were calculated (R2*=1/T2*). Thereafter, the intra-class correlation coefficient (ICC) was used to check the consistency. All rabbits were killed after MR examination and routine assays were performed for testing the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) in the ear vein blood serum. The contents of total superoxide dismutase (SOD), malondialdehyde (MDA) and myeloperoxidase (MPO) in liver tissues were determined, and histopathological changes were examined. The correlation between R2* value and clinical test index was evaluated by Spearman correlation analysis. The R2* value was evaluated by ROC curve. Result ICC=0.87>0.75, suggesting that the repeatability of the outcome is good. Compared to the normal control group, R2* value of the warm ischemia-reperfusion injury group was increased (P=0.000). The differences in ALT, AST, LDH, total SOD, MDA and MPO between the two groups were statistically significant (P 0.6, P<0.05), and there was a significantly negative correlation between R2* and total SOD (r=-0.663, P=0.001). The R2* value could efficiently diagnose rabbit hepatic WIRI (AUC=0.99) with the best diagnostic threshold being 116.40 Hz. Conclusion 3.0T BOLD MRI can accurately and non-invasively assess the pathophysiologic changes caused by WIRI. It is of great importance for 3.0T BOLD MRI in dynamically monitoring and evaluating hepatic WIRI. Key words: Rabbits; Hepatic; Ischemia-Reperfusion injury; BOLD MRI