Size,location and patency of the minor duodenal papilla as determined by dye‐injection endoscopic retrograde pancreatography

Background: The accessory pancreatic duct (APD) sometimes is developmentally obliterated near the duodenum. We evaluated patency of the minor duodenal papilla by dye‐injection endoscopic retrograde pancreatography to determine whether patency was related to papillary size and location. Methods: We injected 2–3 mL of contrast material containing indigocarmine into the main pancreatic duct via an endoscopic catheter in 104 patients. It was endoscopically observed whether dye was extruded from the minor papilla. Size of the minor papilla and distance from the orifice of the major duodenal papilla to the apex of the minor papilla were measured endoscopically with measuring forceps. Results: The APD was patent in 56 of 104 cases (54%). Size of the minor papilla varied considerably from 3 to 6 mm, but showed no correlation with patency. Half of the patients with chronic pancreatitis (6/13) had the minor papilla larger than 6 mm. In cases where the terminal APD had a cudgel or tapering‐off configuration, the minor papilla was larger than in cases where the duct had a stick shape. The minor papilla was patent in 9 out of 10 cases (90%) when it was near the major papilla (≤ 1.5 cm). Frequency of a patent minor papilla was 16 out of 33 (48%) when it existed 1.5 to 2.0 cm from the major papilla, and 31 out of 61 (51%) when the distance was more than 2.0 cm. Conclusions: The minor papilla was more frequently patent when it was close to the major papilla (P < 0.05).