Small prophylactic pancreatic duct stents: an assessment of spontaneous passage and stent-induced ductal abnormalities

Background and study aims: Placing small stents in the pancreatic duct at endoscopic retrograde cholangiopancreatography reduces the risk of pancreatitis. However, this practice means that a second procedure might be required to remove the stent, and stents can also damage the duct. The aims of this study were to determine the frequency of spontaneous dislodgment and to assess the incidence of stent-induced ductal irregularities. Patients and methods: We performed a retrospective analysis of consecutive patients seen over a 3-year period (2001-2004) who had undergone placement of a 3-Fr pancreatic duct stent and in whom the fate of the stent had been documented. Radiographs were reviewed to determine stent passage at 30 days. If applicable, follow-up pancreatograms were reviewed to assess for stent-induced ductal abnormalities. Statistical analysis was performed using chi-squared and Fisher's exact tests for proportions, and 95 % binomial confidence intervals (CI) were calculated. Results: Records for 125 consecutive patients who had had 3-Fr pancreatic stents placed were reviewed. The stents had passed spontaneously within 30 days in 110/125 patients (88%). In the remaining 15 patients (12%, 95% Cl 6.9%-19%), the stents were still present on follow-up radiographs after a median time of 36 days, (range 31-116 days). Stent length, pancreatic sphincterotomy, and pancreas divisum had no effect on the likelihood of spontaneous passage. No stent-induced ductal irregularities were observed. Conclusions: Nearly 90% of prophylactic 3-Fr pancreatic duct stents pass spontaneously within 30 days, and these stents were not observed to induce changes in the pancreatic duct.