Supplementary Material for: Comparison Study between Double Bare Covered and Fully Covered Metal Stent during Endoscopic Ultrasound-Guided Choledochoduodenostomy (with Video)

Background: Endoscopic ultrasound-guided choledochoduodenostomy (EUS-CDS) is a common technique for biliary drainage. However, EUS-CDS is associated with adverse events such as cystic duct obstruction, stent dislocation, and stent kinking caused by powerful axial force. A novel double-bare, covered self-expandable metal stent (DBSEMS) has recently become available in Japan. This pilot study evaluated the clinical outcomes of EUS-CDS using DBSEMS. Method: We retrospectively enrolled patients with malignant lower bile duct obstruction who underwent EUS-CDS due to failed endoscopic retrograde cholangiopancreatography (ERCP). EUS-CDS procedures performed between April 2017 and March 2018 used a conventional fully covered self-expandable metal stent (FCSEMS), and those performed between April 2018 and April 2019 used DBSEMS. In all stents, the diameter was 10 mm and length was 6 cm. Results: A total of 22 patients underwent EUS-CDS, performed using conventional FCSEMS (n = 12) and DBSEMS (n = 10). Four complications occurred with FCSEMS: cholangitis due to kinking (n = 3) and stent dislocation (n = 1). With DBSEMS, there were no instances of kinking, and reflux cholangitis that developed in 1 patient due to duodenal obstruction was resolved by duodenal stenting. Elapsed time to recurrent biliary obstruction was longer with DBSEMS than FCSEMS (200 vs. 99 days), although the difference was not significant (p = 0.06). Conclusion: BSEMS can help prevent cholangitis due to stent kinking after EUS-CDS, thus increasing stent patency.

背景：内镜超声引导下胆管十二指肠吻合术（Endoscopic ultrasound-guided choledochoduodenostomy, EUS-CDS）是胆道引流的常用术式。然而，EUS-CDS可伴随多种不良事件，例如胆囊管梗阻、支架移位，以及由强轴向力引发的支架成角。近期日本推出了一款新型双裸覆膜自膨式金属支架（double-bare, covered self-expandable metal stent, DBSEMS）。本先导研究评估了采用DBSEMS实施EUS-CDS的临床结局。
方法：我们回顾性纳入了因内镜逆行胰胆管造影（endoscopic retrograde cholangiopancreatography, ERCP）失败而接受EUS-CDS的恶性低位胆管梗阻患者。2017年4月至2018年3月期间开展的EUS-CDS手术采用传统全覆膜自膨式金属支架（fully covered self-expandable metal stent, FCSEMS），2018年4月至2019年4月期间的手术则采用DBSEMS。所有支架的直径均为10mm，长度为6cm。
结果：总计22例患者接受了EUS-CDS，其中传统FCSEMS组12例，DBSEMS组10例。传统FCSEMS组共发生4例并发症：支架成角所致胆管炎3例，支架移位1例。DBSEMS组未出现支架成角病例，仅1例患者因十二指肠梗阻发生反流性胆管炎，经十二指肠支架置入术后症状缓解。DBSEMS组至复发性胆道梗阻的时间长于FCSEMS组（200天 vs 99天），但差异无统计学意义（p=0.06）。
结论：DBSEMS可有效预防EUS-CDS术后因支架成角引发的胆管炎，从而延长支架通畅维持时间。