Reconstruction of middle hepatic vein (MHV) tributaries is controversial in right-lobe living donor liver transplantation (LDLT). This study aimed to evaluate the appropriateness of reconstructing MHV tributaries by volumetry using 3-dimensional computed tomography (3D-CT). Between November 2003 and January 2005, 42 donor livers (right-lobe graft, n = 25; left-lobe graft, n = 17) were evaluated using this software. The total congestion volume (CV) associated with the MHV tributaries and the inferior right hepatic vein (IRHV), and graft volume (GV) were calculated. In recipients with right-lobe grafts, CV/(right liver volume [RLV]) and (GV - CV)/(standard liver volume [SLV]) were compared between 2 groups: with reconstruction (n = 16) and without reconstruction (n = 9). To evaluate the influence of CV on the remnant right lobe in donors, total bilirubin was compared between 2 groups: high CV (CV > 20%, n = 13) or low CV (CV < or = 20%, n = 4). The mean CV/RLV ratio was 32.3 +/- 17.1% (V5, 15.2 +/- 9.9%; V8, 9.2 +/- 4.1%; and IRHV, 8.5 +/- 11.4%) and the maximum ratio was as high as 80.8%. The mean (GV - CV)/SLV ratio before reconstruction in patients with or without reconstruction resulted in 33.5 +/- 12.8% and 55.4 +/- 12.9%, respectively (P < 0.01). In donors, total bilirubin was significantly high in the high CV group on postoperative day 1 compared with the low CV group (P < 0.05). In conclusion, calculation of CV using 3D-CT software proved to be very useful. We concluded that this evaluation should be an integral part of procedure planning, especially for right-lobe LDLT.