BACKGROUND: ERCP by means of long-limb Roux-en-Y surgical anastomoses has been reported primarily in patients with biliary or pancreatic anastamoses, but rarely in patients with an intact papilla. METHODS: All ERCP procedures attempted over a 6-year interval in patients with Roux-en-Y gastrojejunostomies and an intact papilla were reviewed. Patients with a prior Billroth II operation or alteration of the major papilla were excluded. Cannulation and therapy were primarily performed with a duodenoscope after exploration and placement of a guidewire in the afferent limb with a forward-viewing colonoscope. In some cases the duodenoscope was pulled into the afferent limb with a wire-guided balloon passed retrograde into the afferent limb. A follow-up of 30 days was obtained for all patients as part of a prospective ERCP outcome study. RESULTS: Of 15 patients in whom ERCP was attempted, the papilla was reached in 10 patients (67%), the bile duct being accessed in all 10. Needle-knife precut papillotomy after placement of a pancreatic duct stent was performed in 3 patients. Biliary sphincterotomy with a variety of techniques was successful in all 9 patients in whom it was attempted. Other maneuvers included stone extraction, sphincter of Oddi manometry, and biliary stent placement. Final diagnoses were sphincter of Oddi dysfunction (6), malignant biliary stricture (2), choledocholithiasis plus tumor (1), and choledocholithiasis (1). Complications occurred after 3 (12%) of 25 ERCP procedures including pancreatitis (1 mild, 1 moderate) and bleeding (1 mild), all in patients with sphincter of Oddi dysfunction. CONCLUSIONS: Diagnostic and therapeutic ERCP was ultimately successful in two thirds of patients with long-limb gastrojejunostomies and an intact papilla. The success of the ERCP is determined primarily by ability to advance a duodenoscope through the afferent limb. Once the major papilla was accessed with a duodenoscope, advanced biliary and pancreatic therapeutic techniques were feasible.