Impact of the Inferior Right Hepatic Veins on Right Liver Lobe Regeneration in Living-Donor Liver Transplant: 3-Dimensional Computed Tomography Scan Analyses in Donors and Recipients

Outcomes of living donor liver transplant recipients receiving grafts with the graft-to-recipient weight ratio less than 0.6%: A matched pair analysis

We sometimes experience living donor liver transplantation (LDLT) involving very small grafts with graft-to-recipient weight ratio (GRWR) < 0.6% when the actual graft size is smaller than predicted. The outcomes in this situation have not been fully investigated. The present study aimed to determine the graft outcomes of LDLT with GRWR < 0.6%. We retrospectively reviewed 280 cases of adult LDLT performed at our institution between January 2000 and March 2021. In our institution, the lower limit for graft volume/standard liver volume ratio was 30%. The patients were divided into 2 groups according to the cutoff value of 0.6% for actual GRWR. Graft survival and surgical outcomes, including small-for-size syndrome (SFSS), were compared between the groups using propensity score matching analysis. Risk factors associated with SFSS in recipients with GRWR < 0.6% were also evaluated. Fifty-nine patients received grafts with GRWR < 0.6%. After propensity score matching, similar graft survival rates were observed for GRWR < 0.6% (n = 53) and GRWR ≥ 0.6% (n = 53) ( p = 0.98). However, patients with GRWR < 0.6% had a significantly worse 3-month graft survival rate (86.8% vs. 98.1%, p = 0.03) and higher incidence of SFSS ( p < 0.001) than patients with GRWR ≥0.6%. On multivariate analysis, Model for End-Stage Liver Disease score and donor age were associated with SFSS in patients with GRWR < 0.6%. The same factors were also associated with graft survival. In conclusion, although similar overall graft survival rates were observed for LDLT with GRWR < 0.6% and GRWR ≥ 0.6%, GRWR < 0.6% was associated with an increased risk of SFSS. Appropriate donor and recipient selection is important for successful LDLT with very small grafts.

A Hepatectomy Based on a Hybrid Concept of Portal Perfusion of Anterior Segment and Venous Drainage Area of Superior Right Hepatic Vein

BACKGROUND

Right hepatic vein sometimes could not be a reliable landmark between the anterior and posterior segment. The aim of this study was to clarify the portal perfusion area of the anterior segment and to propose a less invasive hepatectomy based on both the portal perfusion and the hepatic venous drainage.

METHODS

Three-dimensional computerized tomography images of 66 patients were constructed. A case, in which the perfusion area of the anterior segment crossed over superior right hepatic vein (SRHV), was called as SRHV-inclusion. It was defined as inclusion of more than 1 cm of the proximal site of SRHV surrounded by the portal perfusion area of the anterior segment.

RESULTS

SRHV-inclusion was observed in 26%. The cases with large inferior right hepatic vein (IRHV) had more frequent SRHV-inclusion (47%). The elderly patient with hepatic disorder, who had hepatocellular carcinoma near the root of the SRHV, underwent a less invasive hepatectomy (anterior segment + SRHV drainage area) resulting in the preservation of the IRHV.

CONCLUSIONS

The perfusion area of the anterior segment crossed over SRHV in one fourth of patients in the study. Our proposed less invasive hepatectomy based on a hybrid concept might be an alternative operative procedure other than right hepatectomy.

Is right lobe liver graft without main right hepatic vein suitable for living donor liver transplantation?

BACKGROUND

Since the first living donor liver transplantation (LDLT) was performed by Raia and colleagues in December 1988, LDLT has become the gold standard treatment in countries where cadaveric organ donation is not sufficient. Adequate hepatic venous outflow reconstruction in LDLT is essential to prevent graft congestion and its complications including graft loss. However, this can be complex and technically demanding especially in the presence of complex variations and congenital anomalies in the graft hepatic veins.

CASE SUMMARY

Herein, we aimed to present two cases who underwent successful right lobe LDLT using a right lobe liver graft with rudimentary or congenital absence of the right hepatic vein and describe the utility of a common large opening drainage model in such complex cases.

CONCLUSION

Thanks to this venous reconstruction model, none of the patients developed postoperative complications related to venous drainage. Our experience with venous drainage reconstruction models shows that congenital variations in the hepatic venous structure of living liver donors are not absolute contraindications for LDLT.