Background and aim: Difficulties and complications during endoscopic retrograde cholangiopancreatography (ERCP) can depend on the anatomy of the papillae, the pathology of the biliary tree, and proper selection of the endoscopic technique. However, knowledge about these relationships is limited.
Methods: This single-center retrospective study included 1002 patients who underwent ERCP. The analyses included the impact of the existing anatomy (shape of the papillae [modified Haraldsson classification], periampullary diverticulum [PAD], common bile duct [CBD] diameter ≤9 mm, outflow obstruction level and choledocholithiasis]) on cannulation difficulty, access technique (classic sphincterotomy [CS], classic precut [CPC], needle precut [NPC], two-step access, unintended Wirsung duct cannulation) and complications (bleeding, hyperamylasemia, pancreatic pain and postendoscopic pancreatitis [PEP]). Results: According to the modified Haraldsson classification,47.4% of the papillae were type 1, 31.3% were type 2; 11.1% were type 3, and 10.2% were type 4. Cannulation was considered difficult in 56.9% (58/102; p=0.0014) of type 4 papillae and 46.4% (162/349; p= 0.001) and 49.5% (46/93; p=0.039) of patients with distal and medial CBD obstruction, respectively. CPC was used for 42.2% (43/102; p=0.017) of patients with type 4 papillae. NPC was used 38.7% (43/111; p<0.0001) of patients with type 3 papillae, and 26.0% (34/131; p=0.008) of patients with a CBD diameter ≤9 mm. Two-step access was used for 28.4% (29/102; p<0.0001) of type 4 papilla patients, 17.8% (53/315; (p= 0.002)) of type 2 papilla patients and 18.9% (66/349; p=0.002)of patients with distal CBD obstruction. Bleeding occurred for 21.9% (104/475; p=0.003) of type 1papilla patients. A total of 19.0% (85/448,p<0.0001) of patients with CBD diameters ≤9 mm had hyperamylasemia; 6.2% (28/449,p=0.025); had pancreatic pain and 4% (18/449; p=0.021)had PEP .
Conclusion: The existing anatomy of the papillae and biliary tree affected the difficulty of cannulation, the selection of access technique, and the occurrence of side effects.