Three-dimensional computed tomography analysis of variations in the middle hepatic vein tributaries: proposed new classification

Purpose: To evaluate the anatomical variations in the middle hepatic vein tributaries (V5/V8) for determining the reconstruction strategy in right lobe living donor liver transplantation (LDLT). Methods: The V5/V8 variations were examined in 268 patients and were classified into three and two types, respectively. The reconstruction rate (RR), patency rate (PR) and clinical outcomes were retrospectively evaluated in 46 right lobe LDLT cases. Results: In terms of V5 variations, the RR and PR were significantly higher for type 2 than type 3 (82.6 vs. 44.4 % and 73.7 vs. 25.0 %, respectively). The alanine aminotransferase level on postoperative day (POD) 5 in the V5 patent group was significantly lower than in the occluded group (123 vs. 191 IU/dL). Regarding V8 variations, the RR and PR were significantly higher for type 1 than type 2 (44.4 vs. 17.6 % and 75.0 vs. 33.3 %, respectively). The aspartate aminotransferase level on POD 3 was significantly lower in the V8 patent group than in the occluded group (50 vs. 121 IU/dL). Conclusion: For right lobe grafts with single large V5 (type 2) or V8 (type 1) variations, reconstruction is necessary. Our new classification of the MHV tributaries is useful for determining the reconstruction strategy to use in right lobe LDLT.