Abstract: Objective To investigate the change of liver stiffness and its correlation with serum markers and pathogenic factors in biliary patients after biliary drainage by 3.0T magnetic resonance elastography(3.0T magnetic resonance elastography). Methods 70 patients with biliary tract diseases diagnosed and treated in our hospital between June 2020 and December 2022 were enrolled. Among them, 35 patients were diagnosised with biliary obstruction and underwent biliary obstruction relief surgery. Liver stiffness was detected by 3.0T magnetic resonance elastography, and blood biochemical indexes were detected by automatic biochemical analyzer. The clinical data of patients with biliary obstruction and non-biliary obstruction were compared. Results The liver stiffness values, total bilirubin, TBA, ALT, AST and GGT levels in patients with non-biliary obstruction were (2.3±0.4) kPa, (9.9±3.8) μmol/L, (4.8±1.5) μmol/L, (65.1±14.2) IU/L, (35.1±8.5) IU/L, and (71.7±12.3) IU/L, respectively, which were significantly lower than those in patients with biliary obstruction [4.5±1.1) kPa, (248.6± 45.2)μmol/L,(53.6±8.4)μmol/L,(136.8±16.5)IU/L,(99.8±28.7)IU/L and(464.2±53.9)IU/L,P<0.05]; Among patients with non-biliary obstruction, the number of patients with pathogenic benign factors was 20, which was significantly higher than that of patients with biliary obstruction in 11. The number of patients with pathogenic malignant factors was 15 cases significantly less than that of patients with biliary obstruction (P<0.05). The liver stiffness of patients with non-biliary obstruction were (2.3±0.4) kPa and (2.3±0.3) kPa lower than those of patients with biliary obstruction [(3.7±0.9) kPa, (4.7±0.9) kPa, P＜0.05], respectively; In patients with biliary obstruction, the liver stiffness (4.7±0.9) kPa in patients with malignant causative factors was significantly higher than that in patients with benign causative factors [(3.7±0.9) kPa, P ＜0.05]; The liver stiffness was highly linearly correlated with the serum total bilirubin and GGT levels (r₁=0.657, r₂=0.545, P＜0.01), and was linearly correlated with the serum ALT and AST levels (r₁=0.334, r₂=0.312, P＜0.01), and 35 patients with biliary obstruction underwent biliary drainage compared with (5.3±0.4) kPa and (226.5±51.4) μmol/L. After surgery, the liver stiffness and bilirubin level significantly decreased [(2.5±0.3) kPa, (16.5±4.2) μmol/L, P＜0.05, respectively]. Conclusion 3.0T MRE showed that liver stiffness was increased in patients with obstruction, which is not related to benign or malignant causative factors, but could decrease after early relief of biliary obstruction. Therefore, the measurement of liver stiffness by 3.0T MRE can be used as a non-invasive detection standard to predict the effect of biliary decompression after biliary drainage, which is worthy of clinical application.

Key words: Biliary obstruction, Cholestasis, Liver stiffness, Magnetic resonance elastography