Effect of the extrahepatic bile duct anatomy on choledocholithiasis and its clinical significance

Figure 1 Cross-section of the bile duct and insertion height of the cystic duct is divided into three equal segments. A: Insertion position of the cystic duct is divided into anterior, posterior, medial, and lateral segments; B: Insertion height of the cystic duct is divided into upper, middle, and lower segments.

Figure 2 Cystic duct typing. I: Linear type; II: Curve type; III: Spiral type; IV: Complex type.

Figure 3 Morphology of the common bile duct. A: Polyline type; B: S type.

Figure 4 Oblique angle of the common bile duct and angle of the common bile duct. α indicates the oblique angle of the common bile duct: Angle between the first bend of the common bile duct and the horizontal line; β indicates the angle of the common bile duct: First angle between the common bile duct and the ampulla.