Anatomical Variations of the Portal Vein Trunk and Confluence Using Multispiral Computed Tomography

For a long period of time, cadaveric material was used to study the anatomy of the portal vein system; however, more reliable results can be obtained using in vivo imaging techniques. The aim of our study was to investigate the topographic-anatomical features and morphometric characteristics of the portal vein trunk and confluence using multispiral computed tomography (MSCT). Material and methods . Anatomical variations of the portal vein trunk and confluence was studied by analyzing abdominal MSCT results from 80 patients with no evidence of liver, pancreatic, or splenic diseases, as well as portal hypertension. Results . In the sample we studied, the formation of the portal vein confluence demonstrated significant variability: in 44 cases, the inferior mesenteric vein drained into the splenic vein; in 31 cases, into the superior mesenteric vein; and in 5 cases, this vessel emptied into the angle of confluence of the superior mesenteric and splenic veins. The level of the portal vein confluence varied from the superior border of the L I vertebra to the inferior border of the L III vertebra, which generally correlated with the level of the portal vein bifurcation into its lobar branches. It was found that all the studied parameters demonstrated significant variability; however, the greatest variability was characteristic of the confluence angle. Conclusion . The wide range of all studied parameters in the general sample indicates the necessity for further research that takes into account the sexual, age, and typological characteristics of the portal vein system vessels.