Gross Anatomical Variations and Congenital Anomalies of Surgical Importance in Hepatobiliary Surgery in Uganda.

Background: It is important for surgeons to appreciate the possible anatomical variations that can be encountered during surgery. This study was aimed at determining the gross anatomical variations and congenital anomalies of the external hepatobilliary system in Ugandan cadavers and to describe the nature and contents of the gallbladder among cadavers of Ugandans. Methods: This was a cross-sectional study done at the Department of Anatomy Dissection Laboratory at Makerere University Medical School in Kampala, Uganda. The study involved all cadavers dissected in a period of 8 years, from October, 1997 to June 2005, 21 each year, totaling 168 cadavers. Results: A wide range of Anatomical variations of surgical importance were noted among the Ugandan cadavers. In 5% of the cases, the common hepatic artery originated from the superior Mesenteric artery. The course of the cystic artery in 61.9% of the cases was anterior to the right hepatic duct, in 31% it passed anterior to the right hepatic duct, in 8% it lied posterior to the common bile duct, and in 25% of cases, there were more than 2 cystic arteries. In 56% the common hepatic artery branched some 2 - 4cm away from the porta hepatis, 4% branched within the substance of the liver, 19% at the level of porta hepatis while in 5% it branched at the level of right gastric artery. The cystic duct branched off from the common Hepatic duct in 95% of specimens while in 5% originated from the right hepatic duct. Joining of the common hepatic duct contributed to low branching accounting for 67% while 19% had high branching level from the duodenum. The length of the common bile duct ranged from 2.5cm to 12cm, the mode being 4cm and the average 5.1cm. In 4% of the cadavers there were multiple stones with the gallbladder being adherent to neighbouring viscera. Conclusion: The results show that within the Ugandan population, there are marked variations of surgical importance in the gross anatomic features of the hepatobiliary system, which need to be considered to in order to avoid errors during gallbladder or extra hepatic biliary surgery.