recently , there has been a considerable increase in the number of hepatectomies and mortality rates reduced to less than 5% .
nevertheless , surgical approach to centrally located tumours close to the confluence of the hepatic veins is still a challenging issue .
trisectionectomies are considered the first option but are associated with high mortality rates due to post - operative liver failure .
recent studies showed that liver parenchymal damage may play a role in tumour cells and their micro - environment .
thus , major hepatectomies with intense post - operative regeneration or segmentectomies that leave parenchyma without adequate venous drainage may not be the best treatment for hepatic malignancies .
we performed a segment 8 hepatectomy with resection of a segment of the right hepatic vein followed by immediate reconstruction of the vein with a gore hybrid vascular graft ( w. l. gore & associates , flagstaff , az , usa ) .
it allowed to preserve all but one of  the hepatic segments and provided optimal venous outflow to remaining segments .
this is the first time this technique is performed , and it is a much easier and safer method than other previously reported techniques .
a 54-year - old male patient with no comorbidities presented with liver metastasis of colorectal adenocarcinoma .
he had undergone right hemicolectomy 1 year before and received chemotherapy with folfox followed by bevacizumab . computed tomography ( ct ) disclosed a 4.0  2.0 cm lesion in segment 8 involving the entire circumference of the right hepatic vein ( which was still partially patent ) , extending medially to the middle hepatic vein and posteriorly to the retrohepatic inferior vena cava ( ivc ) ( fig .
1 ) . 
 figure 1:(a ) and ( b ) preoperative ct showing displacement of the tumour and its relationship with the right and middle hepatic veins and the ivc .
( a ) and ( b ) preoperative ct showing displacement of the tumour and its relationship with the right and middle hepatic veins and the ivc .
as the vein was still patent and there was a concern that a considerable amount of parenchyma could be left with insufficient drainage , we proposed to reconstruct the vein with a graft .
the most challenging step of reconstructing the right hepatic vein with a graft is the anastomosis of the graft with the vein in the transected area .
we decided to use the gore hybrid vascular graft because it allows a sutureless anastomosis at one end of the graft as it has a constrained section with a deployment line that allows easy insertion into the vessel .
intraoperative ultrasound ( us ) was performed to define tumour margins and its relationship with vascular structures .
the right hepatic vein was dissected through the loose space between the vena cava and the liver and taped .
transection started at the middle hepatic vein until it was released from the tumour , and proceeded posteriorly to release the tumour from the ivc .
the remaining parenchyma was transected and the right hepatic vein was skeletonized for a length of 1 cm to allow graft placement ( fig .
2 ) . subsequently , the open end of the graft was anastomosed in a standard manner to the ivc ( fig .
3 ) . 
 figure 2:(a ) right hepatic vein sutured close to the ivc .
( d ) retrohepatic ivc , area to be anastomosed to one end of the graft .
figure 3:the open end of the graft being anastomosed to the ivc ( the graft was previously cut to the proper length , approximately 5 cm ) .
( d ) retrohepatic ivc , area to be anastomosed to one end of the graft .
the open end of the graft being anastomosed to the ivc ( the graft was previously cut to the proper length , approximately 5 cm ) .
the constrained section of the graft was introduced ~2 cm inside the vein and the deployment line was pulled ( fig .
4 ) . 
 figure 4:(a ) specimen , ( b ) right hepatic vein and ( c ) graft .
( a ) specimen , ( b ) right hepatic vein and ( c ) graft .
figure 5:final appearance : ( a ) intraoperative appearance and ( b ) schematic drawing .
patient spent 1 day on intensive care unit and was discharged from hospital on post - operative day 6 .
u / l at 5 hours after the procedure and 72 u / l at discharge .
double antiaggregant therapy was initiated on the second post - operative day with clopidogrel ( 75 mg orally daily ) and aspirin ( 100 mg orally daily ) .
one month after the procedure , clopidogrel was interrupted and aspirin maintained as single - antiplatelet therapy . doppler us on post - operative day 2 showed normal blood flow in the graft .
contrast - enhanced ct scans performed on post - operative day 5 and 3 months after the procedure showed a properly positioned and patent graft ( fig .
figure 6:ct scan performed on the fifth post - operative day : ( a ) axial view , no intravenous contrast ; ( b ) axial view , intravenous contrast inside the graft and ( c ) coronal view , graft filled with contrast .
ct scan performed on the fifth post - operative day : ( a ) axial view , no intravenous contrast ; ( b ) axial view , intravenous contrast inside the graft and ( c ) coronal view , graft filled with contrast .
 hepatectomies have evolved . in recent years , the goal is to preserve as much hepatic segments as possible .
however , we are entering a new era , in which not only the liver segments , but also the hepatocytes are the focus of attention .
the intention is to produce as little damage as possible to hepatocytes , as liver regeneration may create a micro - environment favourable for tumour cell proliferation and have negative impact on oncological outcome [ 36 ] . in this context ,
preservation of hepatic veins is crucial . better understanding of the role of the inferior right hepatic vein and that segment 6 has multiple veins forming numerous anastomoses with surrounding hepatic veins allowed the resection of segments 7 and 8 including the right hepatic vein without its reconstruction [ 2 , 810 ] .
however , atrophy of segment 6 and liver dysfunction / failure occur in most cases [ 2 , 10 ] .
we decided to resect segment 8 with right hepatic vein reconstruction using a vascular graft that allowed easy deployment of the graft into the vessel .
it ensured maximal preservation of functional parenchyma without congestion , limiting post - operative regenerative activity and parenchymal dysfunction ( as judged by low aminotransferase levels ) , with possible oncological benefits .
we described a novel technique that allows preservation of liver segments with natural venous drainage , limiting parenchymal dysfunction .
it is an easy and reproducible method for reconstructing hepatic veins , which may allow this type of reconstruction to be performed more frequently .
 surgical resection is the treatment of choice for malignant liver tumours . 
 nevertheless , surgical approach to tumours located close to the confluence of the hepatic veins is a challenging issue . 
 trisectionectomies are considered the first curative option for treatment of these tumours . 
 however , those procedures are associated with high morbidity and mortality rates primarily due to post - operative liver failure . thus , maximal preservation of functional liver parenchyma should always be attempted . 
 we describe the isolated resection of segment 8 for the treatment of a tumour involving the right hepatic vein and in contact with the middle hepatic vein and retrohepatic vena cava with immediate reconstruction of the right hepatic vein with a vascular graft . 
 this is the first time this type of reconstruction was performed , and it allowed to preserve all but one of the hepatic segments with normal venous outflow . 
 this innovative technique is a fast and safe method to reconstruct hepatic veins . 
Introduction
Operative Technique
Discussion
Conclusion
Conflict of interest statement