Fig. 1. Flow chart of the study participants. EUS-HGS, endoscopic ultrasound-guided hepaticogastrostomy; AG, antegrade; IHBD, intrahepatic bile duct.

Fig. 2. Flow chart of the rescue guidewire technique.

Fig. 3. Measurements of the puncture angle between the fine needle and intrahepatic bile duct on the endoscopic ultrasound (EUS) images (A, C), and the puncture angle between the fine needle and echoendoscope (B, D) on the fluoroscopic images. Successful guidewire manipulation cases: The puncture angle was obtuse (110°) on the EUS image (A) and was also obtuse (135°) on the fluoroscopic image (B). Unuccessful guidewire manipulation cases: The puncture angle was acute (55°) on the EUS image (C) and was also obtuse (135°) on the fluoroscopic image (D).

Fig. 4. Receiver operating characteristic curves for the evaluation of the impact of the puncture angle between the fine needle and the intrahepatic bile duct and the determination of the optimal cutoff value.

Fig. 5. Endoscopic ultrasound and fluoroscopic images of a patient with unsuccessful guidewire manipulation in the B2 puncture group. (A) Abdominal computed tomography reveals swelling of the left lobe. (B) The first puncture angle between the needle and the intrahepatic biliary tract was acute. (C) The guidewire was only inserted into the peripheral bile duct. The scope was not directed toward the hilar side. (D) We re-punctured another bile duct, and the puncture angle between the needle and the intrahepatic biliary tract was obtuse. (E) The guidewire was easily inserted into the hilar bile duct. The scope was toward the peripheral side.

Fig. 6. Rescue methods for unsuccessful guidewire manipulation. EUS-HGS, endoscopic ultrasound-guided hepaticogastrostomy.

Graphical abstract