Analysis Of Correlative Factors Affecting The Incidence Of Inferior Right Hepatic Vein

Purpose With the presentation of the concept of "third porta hepatis" and its important role in hepatic venous blood drainage,the researches about short hepatic vein are more and more profound.The inferior right hepatic vein(IRHV)belongs to one type of the short hepatic veins and has certain incidence in individuals.While performing a IRHV involved hepatectomy,IRHV injury could cause uncontrollable massive hemorrhage.The occurrence of this situation undoubtedly increases the operation time.A large amount of blood loss would inevitably result in ischemia-perfusion injury of the liver and influence the recovery of liver function after surgery.Lots of blood loss must be infused into the patient with a large amount of red blood cells and plasma during surgery.Many studies have shown that large amount of blood transfusions could reduce the body's immunity and result in early recurrence and distant metastasis of hepatic carcinoma.Massive hemorrhage in the process of surgery could also prolong the hospital stays and do harm to enhanced recovery after surgery.A large amount of blood infusion would influence the patients' prognosis and shorten postoperative survival.Hence,it is of great clinical significance for liver surgeons to know the incidence and the anatomical structure of IRHV.The relation among the incidence of IRHV,the diameter of right hepatic vein(RHV),patients' gender,age and the angle between RHV and inferior vena cava(IVC)was studied through the upper abdomen enhanced CT three-dimension reconstruction images.And we could provide the liver surgeons a simple and reliable method for predicting the presence of the IRHV before surgery.Materials and methods CT imaging data of 1980 patients was collected in the Department of Radiology,Qingdao Municipal Hospital from July 1,2016 to July 1,2017.The patients with heart diseases,IVC disease,history of liver surgery or trauma,space-occupying lesions in the liver,as well as any other diseases influencing hepatic hemodynamic changes were excluded in our research.It should be noted that the RHV type of RHV injecting into the IVC using a common trunk with middle hepatic vein and RHV type of RHV number ? 2 was also excluded in our research.299 patients were included in the study.The CT images were reconstructed by three-dimensional reconstruction software AW 4.7 of CT machine workstation.The diameter of RHV,the diameter of IRHV and the angle between RHV and IVC was observed and counted in this study.Results The images of CT three-dimensional reconstruction were clear and reliable.We could easily observe and count the required parameters from various viewpoints by means of rotating the images.Of the eligible 299 patients,84 had only 1 IRHV with the incidence of 28.09%.15 had 2 with the incidence of 5.02%.4 had 3 with the incidence of 1.34%.More than 3 IRHVs were not seen in any patient.The overall incidence of IRHV was 34.45%(103/299).The diameter of the RHV ranged from 3.48 mm to 16.49 mm with an average value of 9.89 mm.The angle between the RHV and IVC ranged from 12.79° to 190° with a median value of 43.98°.Of the 299 patients,230 patients had acute angle with a percentage of 76.92%.10 had right angle with a percentage of 3.34%.59 had obtuse angle with a percentage of 19.74%.The patients' gender,age and the angle between RHV and IVC was not correlated with the incidence of IRHV.The diameter of the RHV had a negative correlation with the incidence of IRHV and the diameter of the RHV was an independent factor influencing the incidence of IRHV(P value<0.05).The area under the diagnostic ROC curve for the incidence of IRHV was 0.878.The diagnostic threshold value of the RHV diameter was 8.86 mm.Conclusions The incidence of IRHV is negatively correlated with the diameter of the RHV,which means the larger the diameter of the RHV is,the higher the incidence of the IRHV is.Vice versa.If the diameter of RHV?8.86 mm,there is no IRHV generally exists.But if the diameter of RHV <8.86 mm,the IRHV usually appears.The incidence of IRHV is not correlated with the patients' gender,age,and angle between the RHV and IVC.The results on incidence of IRHV could provide new ideas for precise hepatectomy,living donor liver transplantation and other liver surgery.