Background: Anatomical variations in right liver lobe are common. However, clinical implications and surgical management of these variations in living donor liver transplantation have not been analyzed systematically.
Methods: Surgical anatomy of vascular and biliary structures in 120 right lobe grafts were reevaluated by reviewing the results of preoperative (computerized tomography and Doppler ultrasonography) and intraoperative (cholangiography) imaging as well as surgical findings. The data were analyzed in relation to surgical management of anatomical variations.
Results: The incidence of variants leading to multiple portal vein anastomoses was 7.5%. The incidence of dual right hepatic veins was 0.8%; 30% of the grafts had significant accessory hepatic veins (>5 mm) and 13.9% of these were multiple. All of them were successfully reconstructed with technical modifications including venoplasty and venous grafts, except for two cases with multiple intraparenchymal portal vein branches to the anterior segment. The incidence of dual hepatic arteries was 1.7%, but only one of them was reconstructed without negative sequelae. The incidence of variants potentially leading to multiple bile duct anastomoses was 35.0%, and eventually 39.2% of the grafts had multiple orifices. With a variety of techniques including ductoplasty, hepaticohepaticostomy, and biliary stent, total incidence of leakage and stenosis was 10.8% and 9.2%, respectively. Although ductoplasty, internal stent or no stenting, seemed to be associated with increased risk of complications, anatomical variants, multiple bile ducts, and duct-to-duct reconstruction did not bear a significant risk.
Conclusions: Anatomical variations of vascular and biliary structures in right lobe grafts are common. However, most can be managed safely with technical modifications. Only cases with intraparenchymal origin of the anterior portal vein(s) may form a relative contraindication, especially when combined with similar biliary variants. Otherwise, intraoperative assessment of biliary anatomy was enough for successful management. Detailed and precise assessment of vascular and biliary anatomy is vital for appropriate surgical management.