Liver elasticity assessment after biliary drainage in patients with extrahepatic cholestasis by shear wave sono-elastography (SWE)

Background Extrahepatic cholestasis that is caused by benign and malignant diseases has been reported to influence liver elasticity, independent of liver fibrosis. Shear wave sono-elastography is a novel noninvasive ultrasound-based tool to assess liver stiffness that is indirectly measured by the propagation velocity of ultrasound waves within the liver parenchyma. The aim of our study is to explore the impact of extrahepatic cholestasis on liver elasticity assessed by sono-elastography. Methods This is the prospective cohort study of 80 patients with obstructive jaundice. Liver elasticity was measured before biliary drainage (day 0), with measures repeated 2 days (day 2) and seven days (day 7) after biliary drainage. Then, correlation with serum bilirubin and serum liver enzymes values was done. Results The studied patients with extrahepatic cholestasis (38 males and 42 females with mean age ± SD of 45.8 ± 14.6 years) referred to our department for biliary drainage. All underwent liver elasticity measurement by real-time shear wave sono-elastography before biliary drainage with the highest value of mean elasticity (± SD) 8.44 kPa (± 3.02) and then repeated on day 2 with mean elasticity 6.82 kPa (± 2.77), followed by maximum improvement of liver stiffness on day 7 with mean elasticity 4.8 kPa (± 1.80), coincided with improvement of cholestatic laboratory levels. Conclusions This study confirmed improvement of liver stiffness, measured by sono-elastography, after biliary drainage in patients with extrahepatic biliary obstruction.