Impact of papillary morphology and diverticular type on needle-knife precut sphincterotomy in patients with periampullary diverticulum with difficult biliary cannulation

Abstract

Background and Aims Several studies have investigated the relationship between the technical success of ERCP and periampullary diverticulum (PAD), but only limited studies have specifically examined advanced cannulation techniques such as needle-knife precut sphincterotomy (NKPS). This study aimed to explore the outcomes of NKPS in patients with PAD. Methods This retrospective study was conducted on 122 patients with PAD who underwent NKPS due to difficult biliary cannulation. Patient characteristics, ERCP indications, CBD diameter, PAD classification, diverticular size, major duodenal papilla (MDP) morphology, and post-ERCP adverse events were assessed. We analyzed factors associated with the outcomes of NKPS in patients with PAD, with a specific focus on the type of PAD and the morphology of MDP. Results Among 122 patients, 82 (67.2%) belonged to the NKPS success group and 40 (32.8%) belonged to the NKPS failure group. Diverticular size was significantly larger in the NKPS failure group. For type I, type II, and type III PAD, the median dimeters of diverticula were 1.2 cm, 0.9 cm, and 0.5 cm, respectively (P<0.001), and the NKPS success rates were 50%, 66.3%, and 75%, respectively (P=0.391). Regarding MDP morphology, the NKPS success rates were 73.7%, 38.2%, 92.9%, and 82.4% for types I, II, III, and IV MDP, respectively (P =0.059). The overall adverse event rate was 16.4%, including pancreatitis (6.6%), delayed bleeding (5.7%), and cholangitis (4.1%). There were no significant differences in adverse event rates between the NKPS success and failure groups. Multivariate analysis showed that MDP morphology (type II vs. type I, OR: 0.256, 95% CI: 0.089-0.734, P=0.011) and bleeding during NKPS (OR: 0.117, 95% CI: 0.039-0.351, P< 0.001) were independent factors associated with NKPS outcome. Conclusions MDP morphology and bleeding during NKPS are independent predictors of NKPS failure in PAD patients with difficult biliary cannulation.