Abstract:Endoscopic retrograde cholangiopancreatography with stent implantation have gradually become the standard palliative care for patients with distal malignant biliary obstruction. Nevertheless, the function of the sphincter of Oddi is eliminated and the normal anatomical structure of the biliary tract is changed with the placement of stents of various materials. As a result, the duodenal contents will likely flow back into the bile duct, leading to a significantly increased probability of cholangitis in patients and seriously affecting the patients' quality of life. In order to reduce the occurrence of associated adverse events such as bile duct reflux, anti-reflux stents have appeared. Most of them are designed by adding an anti-reflux valve at the end of the stent to function as an anti-reflux barrier. They can be categorized into anti-reflux plastic stents and anti-reflux metal stents according to the material, and also can be named by the shape of the anti-reflux valve such as the windsock anti-reflux stents, funnel anti-reflux stents and duckbill anti-reflux stents. A number of clinical studies demonstrated that most anti-reflux stents can not only reduce the occurrence of cholangitis, but also prolong the average patency time of the stent, with favorable clinical results. However, due to differences in the material and design of different types of stents, problems such as stent clogging and stent displacement still require to be further resolved. Here, the authors address the research progress and clinical application of anti-reflux biliary stents with different materials and structures by review of the relevant literature.