Intraductal Stent (“Inside Stent”) Placement for Post Liver Transplant Duct-to-Duct Anastomotic Biliary Strictures: A Feasibility Study

Abstract

Introduction: Placement of a biliary stent entirely within the bile duct above the intact biliary sphincter (“inside stent”) has been shown to decrease the incidence of stent occlusion in animal studies. Biliary sphincter preservation may reduce biliary bacterial colonization and resultant stent occlusion, and also decrease sphincterotomy related complications. Aim: To assess the feasibility of inside stent placement for anastomotic biliary strictures after liver transplantation with duct-to-duct anastomosis. Methods: Patients found to have an anastomotic biliary stricture during ERCP underwent inside stent placement. Biliary endoprostheses (8.5 Fr-10 Fr 5 cm) with one internal flap and with the distal flap removed to allow passage of the stent above the papilla were placed endoscopically during ERCP. The entire stent was intraductal, straddling the stricture, with its distal end above the biliary sphincter. A 7 cm long 2.0 prolene suture was affixed to the distal side-hole of the stent to facilitate removal of the stent. After stent deployment the suture traversed the papilla with its distal end in the duodenum. Results: An inside stent was placed in 10 patients with anastomotic biliary strictures and abnormal liver tests after liver transplantation. Median duration of stenting was 69.5 days (4-113 days) before patients underwent a scheduled follow-up ERCP for stent removal. At subsequent ERCP, normalization of, or >50% improvement in AST, ALT, alkaline phosphatase and total bilirubin was seen in 6/10 (60%), 6/10 (60%), 8/10 (80%) and 9/10 (90%) patients respectively. Stent occlusion based on the 10 cm water cup test was seen in one asymptomatic patient after 83 days. There was no incidence of cholangitis, pancreatitis, bleeding or perforation after inside stent placement or removal. Stents were removed by grasping the suture with a rat-tooth forceps to remove the stent from the duct and then subsequently snared. The suture was pulled off the stent in 1 case and the stent was then removed from the duct with a rat-tooth forceps. At follow-up ERCP, 9 of 10 stents were noted to be in good position (1 stent migrated upstream above the stricture). Of the 9 patients with improvement in bilirubin after inside stenting, 3 patients required further endoscopic therapy (2 with sphincterotomy and transpapillary stenting and 1 with biliary sphincterotomy alone). Conclusions: Biliary inside stent placement is a safe, feasible, sphincter-preserving option for therapy of anastomotic biliary strictures after liver transplantation. Further studies comparing inside stents with standard transpapillary stents in the post-transplant setting are required.