Patency of the accessory pancreatic duct in relation to its course and shape: a dye-injection endoscopic retrograde pancreatography study.

Abstract

The accessory pancreatic duct (APD) exhibits several appearances on pancreatography. We examined the patency of the APD by dye-injection endoscopic retrograde pancreatography (ERP), and studied the relationship between patency and duct course and shape. There were 213 patients with satisfactory imaging of the entire normal APD who also underwent dye-injection ERP. The length and maximum diameter of the APD and the length of the main pancreatic duct (MPD) from its orifice to the junction with the APD were measured. The caliber of the patent APD was 1.6 +/- 0.6 mm. This was significantly larger than the caliber (1.1 +/- 0.4 mm) of the nonpatent APD (p < 0.01). The length of the MPD from its orifice to the junction with the patent APD was 32.7 +/- 12.5 mm. This was significantly longer than the length to the junction with the nonpatent APD (22.5 +/- 8.1 mm) (p < 0.01). The APD was classified according to duct course: long type, intermediate type, short type, or ansa type. Patency was most common in the long type APD (74.5%). The terminal shape of the APD was also used to classify the ducts: stick type, branch type, saccular type, cudgel type, or spindle type. Patency was most frequently observed in the spindle and cudgel type ducts. Patency of the APD might be dependent on duct caliber, course, and terminal shape of the duct.