Peripheral portal vein-oriented non-dilated bile duct puncture for percutaneous transhepatic biliary drainage

Figure 3 This technique increased the possibility of the puncture needle crossing the targeted non-dilated bile duct, and also provided an appropriate angle to insert the drainage catheter for the next step. A: The insertion angle between the puncture needle and running course of the bile duct (BD) should be less than 30°; B: Under ultrasonographic guidance, percutaneous transhepatic puncture is performed along the running course of the targeted peripheral non-dilated BD (B6 for right-sided approach) or along the accompanying portal vein (P6) when the BD is not well visualized. This technique can provide an appropriate insertion angle of less than 30° between the puncture needle and BD running course.