Clinical Significances of Variants and Anomalies of Cystico-Hepatic Junction by Endoscopic Retrograde Cholangiography

Park, Jong Jae; Lee, Hong Sik; Kim, Chang Duck; Ryu, Ho Sang; Hyun, Jin Hai

Abstract

BACKGROUND/AIMS: The biliary tract often shows various morphologic abnormalities. Thus various anomalies and variations of the cystic duct have been extensively studied via cadeveric or intraoperative dissections and operative cholangiograms. The knowledge of the junction of cystic and common hepatic duct is essential for endoscopic management of biliary tract disease. But no large series identifying this critical cystico-hepatic junction(CHJ) by duodenoscopy has been reported.
METHODS
To know the anomaly and variant of CHJ and to evaluate its clinical significence, we retrospectively reviewed 434 cases of endoscopic retrograde cholangiography performed at Korea University Hospital from 1992 through 1993. The CHJ was categorized as lateral or medial only for unequivocal angulation in that direction, and spiral when there is overlap of the CHJ with the bile duct in the posteroanterior view. The CHJ was further modified as parallel if the course of the two ducts was closely adherent for 1 cm or more. In addition to identifying the radial takeoff, the level of the CHJ along the length of the extrahepatic biliary tree was determined. The distance from the ampulla to the junction was divided by the distance from the ampulla to the bifurcation and expressed as proximal, middle, distal, respectively.
RESULTS
The level of CHJ was mainly middle in 68.4% followed by distal in 16.4%, prximal in 15.2%. The radial orientation of CHJ was mainly lateral in 51.6%, followed by spiral in 32.3%, medial in 16.1%. The cystic duct runs parallely in 11.5%, mainly in the distally inserted, medially oriented cystic duct. The incidence of abnormalous CHJ was 5 case(1.2%), which included 1 case of cystic duct entering the right hepatic duct, 3 case of cystic duct entering at the junction of both extrahepatic duct(trifurcation), and 1 case of accessory hepatic duct entering cystic duct. The most common biliary disease by ERCP was gallbladder stone(25.5%), followed by common bile duct stone(19.5%), intrahepatic duct stone(7.2%), cystic duct obstruction(4.5%), cystic duct stone(2.9%), and others(bile duct cancer, gallbladder cancer, Mirizzi's syndrome). According to the level of the CHJ, there were low incidence of gallbladder stone in distal CHJ, low incidence of common bile duct stone in proximal CHJ and high incidence of Mirrizi's syndrome and gallbladder cancer in distal CHJ. There were no difference in the incidence of biliary disease according to the radial orientation and course of the CHJ. Practically, during therapeutic ERCP there were some tdchnical difficulties in extraction of biliary stone or selective bile duct cannulation in the presence of distally inserted, parallel course of the cystic duct.
CONCLUSIONS
The anatomy of the CHJ by ERCP is more variable than that of previous surgical and autopsy reports and the endoscopist should be aware of this variants for safe and effective intervention in bile duct disease.