Anatomic variations of intrahepatic bile ducts in the general adult Egyptian population: 3.0-T MR cholangiography and clinical importance

Objective

To describe the anatomical variations occurring in intrahepatic bile ducts (IHDs) and their frequencies in general adult Egyptian population using 3.0-T MR cholangiography (MRC) as well as its clinical importance to reduce the biliary complications of hepatobiliary surgery.

Materials and methods

MRC was applied to a study group of 106 subjects (26 potential liver donors and 80 volunteers). Anatomical variations in IHDs were classified based on the variable insertion of right posterior hepatic bile duct (RPHD) using Huang classification.

Results

According to this classification, the frequencies of each type were as follows: Huang A1 (typical pattern): 63.2% (n = 67), Huang A2: 10.4% (n = 11), Huang A3: 17% (n = 18), Huang A4, 7.5% (n = 8), and Huang A5: 1.9% (n = 2). Total frequency for atypical types (i.e. A2, A3, A4 and A5) was 36.8%. No significant difference was detected in the distance between RPHD insertion to the junction of right and left hepatic duct in-between these Huang types. This distance was short (<1 cm) in 21 of subjects under Huang A classification. Twenty-one donors underwent intraoperative cholangiograms, of which twenty (95.2%) had similar classification in both intraoperative and MRC findings.

Conclusion

The incidence of variant biliary anatomy in general Egyptian population (36.8%) as well as the presence of Huang type A with short distance (<1 cm) between RPHD insertion and junction of right and left hepatic duct (19.8%) enhance the importance of MRC as a pre-operative tool before hepato-biliary surgical procedures to reduce post-operative biliary complications.