Hepatic volume profiles in potential living liver donors with anomalous right-sided ligamentum teres

Purpose In living liver donors with rare anatomical anomaly of right-sided ligamentum teres (RSLT), right or left hemiliver procurement is commonly contraindicated. The purpose of this study was to evaluate the hepatic volume profiles in potential donors with RSLT using semi-automated CT volumetry (CTV). Methods Among 5535 potential donor candidates in our institution between April 2003 and May 2019, 23 cases of RSLT (0.4%) were included. Proportional liver volumes were measured using semi-automated CTV and compared with those of manual volumetry and intraoperative graft weights (seven surgical cases). Results The mean percentage volume of the right posterior section was significantly larger than that of the left hemiliver (38.5 +/- 8.4% vs. 23.3 +/- 5.7%,P < 0.001). Particularly in independent right lateral type, the mean percentage volume of the right posterior section was about two times larger to that of the left hemiliver (41.5% +/- 6.5% vs. 21.9% +/- 4.4%,P < 0.001), whereas the volume proportions of these two parts were similar between the two parts in bifurcation and trifurcation types (P = 0.810 and 0.979, respectively). Semi-automated CTV of corresponding whole liver, right posterior section, right anterior section, and left hemiliver showed strong correlations with manual CTV (r = 0.989-0.998;P < 0.001). For the seven surgical cases, the graft weights estimated by semi-automated CTV showed a significant correlation with intraoperative graft weights (r = 0.972;P < 0.001). Conclusion In independent right lateral type of RSLT, the right posterior section tends to be significantly larger than left hemiliver, and may be an alternative option for graft in potential living liver donors with this rare anatomical anomaly.