Bile duct anatomical variations: Relevance for liver division and preparing left split liver grafts for pediatric transplantation: Cohort study

Abstract

Background: liver lateral section graft is the most common graft type used for transplantation in children worldwide. Compared to whole liver grafts, a higher rate of biliary complications has been described. Historically, 2 techniques have been described for transection of liver - trans-hilar or trans-umbilical parenchymal transection. Though these techniques allow dividing the biliary system at two distinct positions, the usual surgical strategies do not take advantage of this advantage.

Material and methods: A retrospective study was conducted on 40 candidates who volunteered for donation of their left lateral liver section for transplantation, between October 2017 and April 2019. Preoperative imaging was analyzed to depict the arterial and biliary anatomy of the liver and their variations, with a dedicated attention to the left liver (segments 2, 3 and 4). Anatomy of the biliary system was taken into account for defining the optimal surgical strategy - either through a trans-hilar or a trans-umbilical parenchymal transection.

Results: In 26/40 patients, arterial or biliary variations were much relevant for decision-making on the optimal plane of liver division (trans-umbilical (N = 14) and trans-hilar (N = 26)). This resulted in 23 grafts with a single artery and bile duct, 6 grafts with double arteries and a single bile duct, and 9 grafts with double bile ducts and a single artery; only two grafts had complex anatomy. There was no arterial complication and the overall incidence of biliary problems was 14.7%. All grafts are functioning well at a mean follow-up of 19.6 ± 8.5 months.

Conclusions: Anatomical variations are frequent and their knowledge is relevant for procurement of lateral section liver graft. Knowledge of these variation, or -better- preoperative biliary imaging is helpful in guiding parenchymal transection at procurement and preparing optimal liver grafts.

Keywords: Bile duct anatomy; Children; Liver division; Liver transplantation; Living donor.