Evaluation of the Feasibility and Effectiveness of Placement of Fully Covered Self-Expandable Metallic Stents via Various Insertion Routes for Benign Biliary Strictures

Management of post-liver transplantation biliary stricture inaccessible by endoscopic retrograde cholangiopancreatography: A case report

BACKGROUND

One challenging scenario in the treatment of biliary stricture is that post-liver transplantation (LT) biliary strictures cannot be accessed using endoscopic retrograde cholangiopancreatography (ERCP). Here, we report such a case that was successfully treated using a novel endoscopic technique.

CASE SUMMARY

A 60-year-old man presented with obstructive jaundice caused by a post-LT biliary stricture. He underwent LT for compensated alcoholic liver cirrhosis and hepatocellular carcinoma. Laboratory investigations unveiled a cholestatic pattern of abnormalities in liver function and a total bilirubin level of 16 mg/dL. Magnetic resonance cholangiopancreatography revealed a stricture extending from the right intrahepatic bile duct into the common hepatic duct. Severe postoperative deformities made accessing the ampulla of Vater with a side-viewing duodenoscope impossible. Percutaneous transhepatic biliary drainage (PTBD) was performed to treat biliary obstruction. Moreover, to resolve the stricture completely, a fully covered self-expandable metal stent (FC-SEMS) with a novel proximal retrievable string was deployed into the post-LT biliary stricture through the PTBD tract. Before inserting the stent through the PTBD tract, the stent with the distal string was manually inverted to ensure that the distal part with the string became the proximal part for later endoscopic removal. After 6 mo, the FC-SEMS was successfully removed without complications, as the string was pulled out using a forward-viewing gastroscope.

CONCLUSION

Deployment and endoscopic removal of an FC-SEMS with a novel proximal string through the PTBD tract may be a viable option for treating post-LT biliary strictures that are inaccessible by ERCP.

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

To assess the feasibility and safety of a novel 3D-printed biodegradable biliary stent using polycaprolactone (PCL) in an in vivo porcine model. In this animal study using domestic pigs, biodegradable radiopaque biliary stents made of polycaprolactone (PCL) and barium sulfate were produced using 3D printing and surgically inserted into the common bile duct (CBD) of pigs (stent group, n = 12). Another five pigs were allocated to the control group that only underwent resection and anastomosis of the CBD without stent insertion. To check the position and status of the stents and stent-related complications, follow-up computed tomography (CT) was performed every month. The pigs were sacrificed 1 or 3 months after surgery, and their excised CBD specimens were examined at both the macroscopic and microscopic levels. Three pigs (one in the stent group and two in the control group) died within one day after surgery and were excluded from further analysis; the remaining 11 in the stent group and 3 in the control group survived the scheduled follow-up period (1 month, 5 and 1; and 3 months, 6 and 2 in stent and control groups, respectively). In all pigs, no clinical symptoms or radiologic evidence of biliary complications was observed. In the stent group (n = 11), stent migration (n = 1 at 3 months; n = 2 at 1 month) and stent fracture (n = 3 at 2 months) were detected on CT scans. Macroscopic evaluation of the stent indicated no significant change at 1 month (n = 3) or fragmentation with discoloration at 3 months (n = 5). On microscopic examination of CBD specimens, the tissue inflammation score was significantly higher in the stent group than in the control group (mean ± standard deviation (SD), 5.63 ± 2.07 vs. 2.00 ± 1.73; P = 0.039) and thickness of fibrosis of the CBD wall was significantly higher than that of the control group (0.46 ± 0.12 mm vs. 0.21 ± 0.05 mm; P = 0.012). Despite mild bile duct inflammation and fibrosis, 3D-printed biodegradable biliary stents showed good feasibility and safety in porcine bile ducts, suggesting their potential for use in the prevention of postoperative biliary strictures.

Percutaneous Transhepatic Treatment of Benign Bile Duct Strictures Using Retrievable Covered Stents: Long-Term Outcomes in 148 Patients

OBJECTIVE

To investigate the long-term outcomes of percutaneous treatment of benign biliary strictures using temporary placement of a retrievable expanded polytetrafluoroethylene (PTFE) covered stent.

MATERIALS AND METHODS

We retrospectively analyzed the outcomes of 148 patients (84 male and 64 female; age range, 11-92 years) who underwent percutaneous transhepatic placement and removal of a retrievable PTFE-covered stent for the treatment of benign biliary strictures between March 2007 and August 2019 through long-term follow-up. Ninety-two patients had treatment-naïve strictures and 56 had recurrent/refractory strictures.

RESULTS

Stent placement was technically successful in all 148 patients. The mean indwelling period of the stent was 2.4 months (median period, 2.3 months; range, 0.2-7.7 months). Stent migration, either early or late, occurred in 28 (18.9%) patients. Clinical success, defined as resolution of stricture after completing stent placement and removal, was achieved in 94.2% (131 of 139 patients). The overall complication rate was 15.5% (23 of 148 patients). During the mean follow-up of 60.2 months (median period, 52.7 months; range, 1.6-146.1 months), 37 patients had a recurrence of clinically significant strictures at 0.5-124.5 months after removal of biliary stent and catheter (median, 16.1 months). The primary patency rates at 1, 3, 5, 7, and 10 years after removal of biliary stent and catheter were 88.2%, 70.0%, 66.2%, 60.5%, and 54.5%, respectively. In the multivariable Cox proportional hazard regression analysis, sex, age, underlying disease, relation to surgery, stricture type, biliary stones, history of previous treatment, and stricture site were not significantly associated with the primary patency.

CONCLUSION

Long-term outcomes suggest that percutaneous treatment of benign biliary strictures using temporary placement of retrievable PTFE-covered stents may be a clinically effective method.