Fig. 2

PTCB for four different imaging features. Case 1 (A–C), a 46-year-old male, had metastatic carcinoma of the hepatic hilum, and preoperative fluoroscopy showed the biliary eccentricity sign (A, arrow). The biopsy forceps were introduced through the 9F sheath, and the PTCB was completed on the obstruction site (B, circle). The pathological result was hilar adenocarcinoma (C). Case 2 (D–F), a 52-year-old female, had a malignant obstruction in the middle segment of the bile duct, and preoperative fluoroscopy showed a local truncation sign (D, arrow). The biopsy forceps were introduced through the 9F sheath, and the PTCB was completed on the obstruction site (E, circle). The pathological result was cholangiocarcinoma (F). Case 3 (G–I), a 76-year-old male, had a lower part of the biliary obstruction. Preoperative cholangiography showed low obstruction with the rat tail sign (G, arrow). The biopsy forceps were introduced through the 9F sheath, the PTCB was completed on the obstruction site (H, arrow), and the pathological result was cholangiocarcinoma (I). Case 4 (J–L), a 50-year-old female, had a hilar obstruction. Cholangiography showed an extensive filling defect sign of the bile duct (J, arrow). The biopsy forceps were introduced through the 9F sheath, and the PTCB was completed on the obstruction site (K, circle). The pathological result was cholangiocarcinoma (L)