Hepatic vein variations in 500 patients: surgical and radiological significance

Abstract

Objectives: The purpose of the study was to assess the incidence of hepatic vein variations on multidetector CT (MDCT) for abdominal examinations. Methods: A retrospective analysis of 534 MDCT scans was performed in patients sent for various abdominal pathologies between January 2017 and April 2019. After excluding 34 patients, finally total of 500 patients (N = 500) were included in the study. For simplification, we classified the hepatic vein variations as classified by Soyer et al, Fang et al and Cheng et al. Results: Single right hepatic vein was seen in 458 (91.6%) out of 500 patients in our study. Two right hepatic veins were seen in 36 patients out of which 27 had common trunk and nine had independent drainage into the inferior vena cava (IVC). Common trunk of middle hepatic vein (MHV) and left hepatic vein (LHV) was seen in 405 (81%) and independent drainage of MHV and LHV into the IVC was seen in 95 (19%) of patients in our study. Amongst the segmental hepatic vein variations, most common drainage of segment IV vein was into LHV (333,66.6%) followed by MHV (148,29.6%) and IVC (19,3.8%). Conclusion: Hepatic vein variations are commonly seen similar to variations in hepatic artery, portal vein and biliary anatomy. Knowledge of these variations is extremely important for transplant surgeons and intervention radiologists. Advances in knowledge: Awareness of the hepatic vein variations is essential for intervention radiologists and surgeons to reduce iatrogenic complications.

Surgical relevance of anatomic variations of the right hepatic vein

“…Therefore, they may also need to be re-implanted at the time of liver transplantation[ 2 , 8 , 18 ]. Although we did not encounter any patients with coexistent MRHV and IRHVs, their coexistence has been reported[ 2 , 4 , 6 , 18 , 36 , 37 , 39 ] and it would increase the technical complexity of right liver transplantation.…”

“…Our literature search returned 26 published studies that evaluated the presence of accessory hepatic veins[ 2 , 4 , 6 , 8 - 37 ]. A variety of study techniques were used.…”

“…Multiple IRHVs have been reported in the medical literature, ranging in incidence from 1%[ 28 ] to 7.3%[ 8 ]. Other complex patterns include multiple IRHV tributaries forming a short common trunk prior to joining the IVC[ 34 , 37 ] or IRHVs with anomalous drainage patterns[ 8 ]. For example, Koc et al [ 8 ] reported an IRHV accepting the adrenal veins to form a common trunk emptying into IVC in two of 1120 individuals.…”

Assessment of the incidence of accessory hepatic arteries: a literature review

“…As the umbilical vein collapses, it is replaced by the portal vein as the main afferent vein. (5,43,44) The formation of the hepatic artery occurs later than the development of the veins. (43) The hepatic artery arises from the aorta and passes through the portal vein in the parenchyma and it gradually expands.…”

“…Postnatal morphology involves blood supply to the liver via the hepatic artery and the portal vein and its outflow through the hepatic veins. (5,43,44) It can be hypothesized that arterial variations such as aLHA and aRHA are caused by differences in embryonic development and are remainder of the left and right embryonic hepatic arteries. (11)…”