Preventive effect of biodegradable stents on biliary stricture and fibrosis after biliary anastomosis in a porcine model

Abstract

Purpose The current drain tubes for preventing surgically biliary anastomotic stricture are not naturally and easily removed. If a drain tube using biodegradable material is easily available and the degradation time of the tube is well controlled, surgical anastomotic stricture and fibrosis could be prevented. The aim of this animal study was to evaluate the preventive effect of novel biodegradable stents (BS) on biliary stricture and fibrosis after duct-to-duct (DD) biliary anastomosis. Methods Ten mini-pigs were allocated to the control group (n = 5) and or the stent group (n = 5). The common bile duct was exposed through surgical laparotomy and then resected transversely. In the stent group, a 4-mm or 6-mm polydioxanone/magnesium sheath-core BS was inserted according to the width of the bile duct, followed by DD biliary anastomosis. In the control group, DD biliary anastomosis was performed without BS insertion. Results In the stent group, stents were observed without deformity for up to 4 weeks in all animals. Eight weeks later, histopathologic examination revealed that the common bile duct of the anastomosis site was relatively narrower in circumference in the control group compared to the stent group. The degree of fibrosis in the control group was more marked than in the stent group (3.84 mm vs. 0.68 mm, respectively; P < 0.05). Conclusion Our study showed that novel BS maintained their original shape and radial force for an adequate time and then disappeared without adverse events. The BS could prevent postoperative complications and strictures after DD biliary anastomosis.

Feasibility and safety of a novel 3D-printed biodegradable biliary stent in an in vivo porcine model: a preliminary study

“…This result suggests that our 3D printed biodegradable biliary stent made of PCL is biocompatible, at least in the porcine model, and is highly unlikely to cause problems in humans. This is similar to the results of previous studies showing good biocompatibility of biliary stents made using PDO during 8- or 20-week follow-up periods in a porcine model 17 , 22 . Regarding human application, Mauri et al 10 demonstrated the safety and effectiveness of the PDO stents for benign biliary strictures with an over 80% patency rate after monitoring 107 cases for two years.…”

“…In addition, fibrosis in the stent group was significantly thicker than that in the control group. According to another previous animal study using PDO biliary stents 22 , the degree of fibrosis in the control group was more marked than that in the stent group at the duct-to-duct biliary anastomosis site. However, in that previous study, the fibrosis thickness of the control group was 3.84 mm, which was significantly thicker than that of our study’s stent group (0.46 mm).…”

“…However, biodegradable materials cannot be visualized as X-rays penetrate the structure. In a previous study 22 , this problem was solved by indirectly visualizing the stent by attaching gold markers to either end of the stent. However, this method has limitations when evaluating the entire stent.…”

Feasibility and Safety of a Novel 3D-Printed Biodegradable Biliary Stent in an In Vivo Porcine Model: A Preliminary Study

“…In addition, brosis in the stent group was signi cantly thicker than that in the control group. According to another previous animal study using PDO biliary stents 22 , the degree of brosis in the control group was more marked than that in the stent group at the duct-to-duct biliary anastomosis site. However, in that previous study, the brosis thickness of the control group was 3.84 mm, which was signi cantly thicker than that of our study's stent group (0.46 mm).…”

Dexamethasone-eluting and self-expandable biodegradable stents suppress fibrosis in biliary stricture

“…Using an in vitro bile flow phantom model, we evaluated degradation time, radial force changes, and morphologic changes of DBBS. Using an in vivo swine bile duct stricture model, we performed a DPOC examination and histopathologic evaluation to observe the biodegradation process and therapeutic effects of DBBS at regular intervals 1 2 3 .…”