Abstract
It is important to understand the anatomy of the cystic duct in laparoscopic cholecystectomy. Three-dimensional magnetic resonance cholangiopancreatography (3D-MRCP) was used to analyze the spatial anatomy of the cystic duct. The subjects were 454 patients who underwent MRCP between April 2005 and March 2016 in our hospital and whose MRCP images depicted the cystic duct branching off from the common bile duct. Examination of the horizontal cross-sections showed that the cystic duct joined the common bile duct from the anterior direction in none of the cases. There was a tendency for the cystic duct to join the common bile duct from the right or left direction when the connection point was at the upstream part or the downstream part of the common bile duct, respectively. When the cystic duct and the common bile duct intersected, the former ran at the dorsal side of the latter, probably because of the clockwise rotation of the duodenum occurring in the fetal stage against the rotationally unchanged upper part of the bile duct fixed to the liver.
