Aim: Pancreatic duct (PD) stents diminish the risk of post endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) in high-risk patients; 3 Fr stents are reported to spontaneously migrate at a significantly higher rate than 5 Fr stents in a cohort of mostly sphincter of Oddi (SOD) patients. We sought to assess spontaneous migration rates of 5 Fr and 7 Fr stents and effectiveness in preventing PEP in a diverse group of high risk patients.
Methods: A total of 4,332 ERCP exams performed between January 2002 and August 2005 were reviewed to identify patients undergoing PD stent placement. Follow-up was obtained from electronic medical records and contact with referring MDs. Plain abdominal radiographs were used to document stent passage.
Results: PD stents for PEP prophylaxis were placed in 246 exams (232 patients) undergoing: PD (major or minor) sphincterotomy (84), ampullectomy (50), SOD (46), bile duct precut (35), papillary stenosis balloon dilation (9) and difficult cannulation (8). Stents placed: 218 5-Fr (140 were 3 cm long and 78 =or> 5 cm long) and 28 7-Fr (12 were 3 cm long, 16=or> 5cm long). Follow-up was available in 197 (171 5-Fr, 26 7-Fr) of 246 placements (80%). Twenty of 171 5-Fr stents were electively removed via EGD within=or< 24 h per endoscopist preference and were not included in analysis; 128 of the remaining 151 5-Fr stents (85%) spontaneously migrated by (or within) median of 8 days and 23 failed to pass and required EGD removal. Of 26 7-Fr stents one was electively removed =or< 24 h later; of the remaining 25, 15 (60%) spontaneously migrated by median of 16 days, 10 required EGD removal. The spontaneous migration rate of 5 Fr stents was: 1) significantly higher than 7 Fr stents; 2) significantly higher than the previously reported 67% passage rate of 5 Fr stents; and 3) similar to the previously reported 86% passage rate of 3 Fr stents. PEP occurred in 15% (n=36: 24 mild, 11 moderate, 1 severe).
Conclusion: The spontaneous dislodgement rate of 5 Fr stents in patients where the indication is primarily non-SOD is approximately 85% - significantly higher than previously reported and similar to the reported rate of spontaneous dislodgement of 3 Fr stents in SOD patients; 5 Fr stents migrate spontaneously earlier and more frequently than 7 Fr stents.