Rare type of course and distribution of an additional right hepatic artery: A possible source of iatrogenic injury during hepato-biliary and pancreatic surgeries

Celiac artery shows frequent variations in its branching pattern. Knowledge of its possible variations is useful in gastric, pancreatic and hepato-biliary surgeries. During our dissection classes, we observed a rare variation of the branching pattern of celiac trunk. It divided normally into its three branches; left gastric, splenic and common hepatic arteries. Left gastric and splenic arteries were normal in their course and distribution. The common hepatic artery trifurcated to give hepatic artery proper, gastroduodenal artery and an additional right hepatic artery. The branching pattern of hepatic artery proper and gastroduodenal arteries was normal. The additional right hepatic artery gave origin to a right gastric artery and a large pancreatic branch to the head of the pancreas. It coursed parallel to the bile duct, being on its right side, passed through the Calot's triangle and entered the right lobe of liver through the fossa for gall bladder. In the Calot's triangle, it gave a cystic branch to the gall bladder. We discuss the clinical importance of this rare variation in this paper.