A Study On Applied Anatomy Of Three-dimensional Reconstruction Of Umbilical Fissure Vein In Liver Surgery

Purpose Hepatectomy had been the first choice therapeutic measure for the treatment of the patients with benign and malignant primary liver lesions and metastatic liver lesions,but there are still risks for intraoperative blood loss and postoperative liver failure.The above-mentioned risks could be reduced by means of the preservation of normal liver tissue as much as possible during the process of hepatectomy without influence of the complete resection of the tumor.It is very important to fully understand the anatomical structure of the liver vessels,especially the anatomical structure of the hepatic veins.The umbilical fissure vein(UFV)is of great significance for the drainage of the left hemi-liver.The UFV is generally located between the S3 and S4 segments of the liver,runs along the umbilical fissure,and primarily drains the hepatic parenchyma of the S3 and S4 segments.The preservation of the UFV allows for greater preservation of normal liver parenchyma,thereby reducing the incidence of postoperative liver failure during the resection of the main hepatic vein refluxing from the UFV.With the advancements of three-dimensional(3D)visualization technology,the application of 3D reconstruction technology to accurately and comprehensively analyze the anatomical structure of UFV could provide sufficient preoperative image evaluations for partial hepatectomy and living donor liver transplantation(LDLT),the safety of liver surgery can enhance.The purpose of this study is to investigate the clinical application value of UFV in liver surgery by means of performing a 3D reconstruction of enhanced CT imaging data to restore the 3D image of UFV.Materials and methodsThe imaging data of 2049 patients underwent the examination of enhanced CT scans in Qingdao Municipal Hospital,Shandong Province were collected from August 2021 to October 2022.The inclusion criteria for this study included the patients had no space-occupying lesions in the liver,did no hilar diseases,did no ampullary,did no inferior vena cava diseases without history of upper abdominal surgery and hepatic vein changes or hepatic hemodynamic changes resluted from other reasons.The enhanced CT images of the upper abdomen in 279 cases who met a criterion were selected.Fifty-six cases were randomly selected from the obtained enhanced CT images of the upper abdomen.The original two-dimensional enhanced CT images of the upper abdomen were uploaded to the Huishi(version 4.0)3D reconstruction software in Vitaworks workstation for 3D reconstruction.In the obtained 3D reconstruction images,the liver was manually selected as the region of interest,while the images affecting the observation of the liver veins such as the kidney and intestinal tract were removed.The diameters of UFV,left hepatic vein(LHV)and middle hepatic vein(MHV)were then observed and counted.ResultsThe Stereoscopic images of the liver by the 3D reconstruction has high contrast and can clearly display the position,course,and diameter of intrahepatic and extrahepatic veins including the UFV,LHV,MHV and IVC.By rotating the image,the desired targets organ can be observed,measured and counted accurately through multiple angles.The incidence of UFV was 78.6%(44/56)in our study.Among the 44 cases,UFV in 36 cases reflux into LHV with an UFV incidence of 81.8%(36/44),UFV in 5cases reflux into MHV with an UFV incidence of 11.4%(5/44)and UFV in 3 cases reflux into common trunk of LHV and MHV with an UFV incidence of 6.8%(3/44).The diameter of UFV ranged from 3.11 mm to 7.34 mm and fulfilled normal distribution with a mean diameter of(4.96 ± 0.96)mm.The 47.7% cases(21/44)had a diameter over than 5 mm.The diameter of LHV ranged from 4.78 mm to 11.21 mm with a mean diameter of(8.03±1.44)mm.The diameter of MHV ranged from 5.69 mm to 13.04 mm with a mean diameter of(8.48±1.54)mm,the incidence of accessory S4 hepatic vein was 39.3%(22/56),the incidence of both UFV and accessory S4 hepatic vein was 30.4%(17/56)and the incidence of neither UFV nor accessory S4 hepatic vein was 12.5%(7/56)in 56 cases.ConclusionThe anatomical structure of intrahepatic and extrahepatic veins including the UFV could be precisely studied by means of 3D reconstruction technology.The incidence of UFV was not associated with age and sex of the patients,the diameter of LHV and MHV.The anatomical relationship between UFV and accessory S4 hepatic vein was not associated with ageand sex of the patients,the diameter of LHV and MHV.The diameter of MHV was significantly positively correlated with the diameter of UFV.When UFV exists,the greater the diameter of MHV,the greater the diameter of UFV and vice versa.When a patient had a MHV with large diameter,the diameter of the patient’s UFV may also be larger.It is very crucial to pay attention to the identification of UFV during the process of hepatectomy.The integrity of UFV in the patients could preserve normal liver parenchyma draining hepatic segment without influence of radical resection of the tumor.It is clinically important for the planning of liver resection to preserve more normal liver parenchyma and to avoid postoperative liver failure without influence of radical tumor resection.The UFV plays an very important role to preserve normal liver tissue as much as possible during the process of radical hepatectomy in the patients with HCC or colorectal cancer liver metastases involving the major trunk of LHV and MHV and in the patients underwent LDLT with the left hepatic lobectomy and left lateral lobe resection of the donor’s liver and how to preserve the MHV.