Liver Graft Volume Estimation by Manual Volumetry and Software-Aided Interactive Volumetry: Which is Better?

Estimation of graft volume is critical in living donor liver transplantation (LDLT). In this study, we aimed to evaluate the accuracy of software-aided automated computer tomography (CT) volumetry in the preoperative assessment of graft size for LDLT and to compare this method with manual volumetry.

Forty-one donors (27 men; 14 women) with a mean age in years ± standard deviation (28.4 ± 6.6) underwent contrast-enhanced CT prior to graft removal for LDLT. A liver transplant surgeon determined the weights of liver grafts using automated 3-dimensional volumetry software, and an abdominal radiologist specializing in liver imaging independently and blindly used the commercial interactive volumetry-assisted software on a viewing workstation to determine the liver volume on CT images. Both results were then compared to the weights of actual grafts obtained during surgery. Intraclass correlation coefficients were used to assess the consistency of numerical measurements and Pearson correlation coefficients were calculated to detect a linear relationship between numerical variables. To compare correlation coefficients, z scores were used.

Regarding the right and left lobe graft volume estimation by the surgeon, there was a positive correlation between the results and actual graft weight (r = 0.834; P = .001; and r = 0.587; P = .001, respectively). Likewise, graft volume estimation by the radiologist for the right and left lobe was also positively correlated with the actual graft weight (r = 0.819; P = .001 and r = 0.626, P = .001, respectively). There was no significant difference between correlation coefficients (P = .836).

Volumetric measurement of donor graft using 3-dimensional software provides comparable results to manual CT calculation of liver volume.