A Novel Taxonomy of Intraoperative Cholangiograms in Suspected Choledocholithiasis: A Tool for Advancing Laparoscopic Common Bile Duct Exploration Outcomes Research

Abstract

Background Cholangiography for visualization of the biliary tree during laparoscopic cholecystectomy is an important diagnostic roadmap in the context of suspected choledocholithiasis (CDL). The renewed interest in transcystic laparoscopic common bile duct exploration (LCBDE) necessitates a general description of the range of CDL presentations. Our aim was to establish a novel classification system of intraoperative cholangiograms (IOCs) to advance research efforts in this field. Methods A novel cholangiogram classification system, featuring 8 distinct presentations of choledocholithiasis, was applied to a data set of 80 preintervention IOCs for suspected choledocholithiasis. The classification system is as follows: A (no common bile duct stones, duodenal filling present, and concern for air bubbles), B (no common bile duct stones, no duodenal filling, and concern for sludge), C1 (stone(s) < 2x size of cystic duct with duodenal filling), C2 (stone(s) < 2x size of cystic duct without duodenal filling), D1 (stone(s) ≥ 2x size of cystic duct with duodenal filling), D2 (stone(s) ≥ 2x size of cystic duct without duodenal filling), E1 (congenital anatomical variant and/or common duct stricture), and E2 (surgically altered biliary anatomy). Results Cholangiogram review yielded preintervention classifications for 6 of 8 variants (A-E): A (7.5%), B (3.75%), C1 (23.75%), C2 (42.5%), D1 (15%), and D2 (7.5%). Analysis of cystic duct diameter yielded no significant differences among classification groups, indicating no predominant pattern of cystic duct anatomy within a given classification. Discussion An IOC classification system for suspected choledocholithiasis is foundational to answering key clinical questions for transcystic laparoscopic common bile duct exploration.