Utility of dedicated bougie dilator for a 0.018‐inch guidewire during EUS‐guided biliary drainage: A multi‐center retrospective cohort study

During endoscopic ultrasound-guided biliary drainage (EUS-BD), a combination of a 19-gauge needle and a 0.025-inch guidewire is generally used. However, a 19-gauge needle has poor maneuverability because of their stiffness and rigidity and might have poor penetrability in non-dilated bile ducts because of their large bore. In contrast, the application of a 22-gauge needle is expected to have improved maneuverability. However, only a 0.018-inch guidewire, which has less supportability, is applicable in the subsequent guidewire selection. This study aimed to evaluate the feasibility and safety of a dedicated bougie dilator for a 0.018-inch guidewire.From September 2019 to May 2020, 26 patients underwent fistula dilation using the dilator after accessing the bile duct using a 22-gauge needle and a 0.018-inch guidewire during EUS-BD. The success and adverse event rates of EUS-BD were evaluated.Biliary access with a combination of a 22-gauge needle and a 0.018-inch guidewire was successful in all with a median bile duct diameter of 5 mm. Dilation of the fistula using the dedicated dilator was also successful in all cases. Subsequently, the dilator was successfully exchanged to an ERCP catheter that allowed for exchange to a 0.025-inch guidewire, except in one case where the catheter did not cross the fistula and a dilation balloon was inserted for an exchange to a 0.025-inch guidewire. The technical success rate of the EUS-BD was 100%. The adverse event rate was 19%.The application of the dedicated dilator for a 0.018-inch guidewire was considered feasible and safe for EUS-BD.