Evaluation of Liver Volume Estimation Methods in Living Donor Liver Transplant: CT Volumetry vs MeVis, With Comparison of Open and Laparoscopic Surgery.

Abstract

Background: Accurately assessing graft volume is crucial for donor and recipient safety in living donor liver transplantation. This can be performed using manual computed tomography volumetry (CTvol) or semiautomated methods (MeVis). We aimed to compare CTvol and MeVis in estimating the actual graft weight during LDLT, and analyse any differences in weight between laparoscopic and open donor hepatectomy.

Methods: A retrospective study of living donors between 2015 and 2022 with complete imaging data was performed. Graft weights were estimated using (1) CT volumetry and (2) semiautomated MeVis software. The primary outcome was graft weight variance ([Predicted weight-Actual weight]/Predicted weight) × 100. The secondary outcome of interest was whether open or laparoscopic surgery affected graft weight variance.

Results: Of the 33 donors, 52.6% were right liver without middle hepatic vein grafts. Nineteen donors (57.6%) underwent open hepatectomy. Both CTvol (r = 0.70; P < .001) and MeVis (r = 0.85; P < .001) showed strong correlation with actual graft weight. Weight variance using CTvol was -2.9% vs -15.3% (P = .04) for open vs laparoscopic, while the corresponding using MeVis was -0.9% vs -8.5% (P = .11). Actual graft-to-recipient weight ratio predicted by MeVis was similar between open and laparoscopic approaches (-0.01 vs 0.07; P = .12).

Conclusions: Both CT volumetry and MeVis showed strong correlation between predicted and actual graft weights. Laparoscopic hepatectomy showed greater variability in graft weight estimation using CT volumetry, but MeVis was similar across both open and laparoscopic surgery.