Anatomical variants of inferior mesenteric vein according on the data of multispiral computed tomography

Knowledge of the variants of the anatomical variability of the liver vascular bed can be of critical importance in liver resection, liver transplantation, laparoscopic operations, resection of the pancreas, surgical treatment of portal hypertension The main vessels of the hepatic portal vein system are characterized by pronounced anatomical variability in the formation of the portal vein trunk, the greatest variability is characterized by inferior mesenteric vein. The aim of the investigation was to study the variant anatomy of the inferior mesenteric vein according to multispiral computed tomography. The material was 100 multispiral computed tomograms of the abdominal organs from the archive of the clinics of the Samara State Medical University for 2018-2019. For mathematical modeling and the creation of threedimensional models based on tomograms of the vascular bed, plugins were used in the programs «Luch» and «Avtoplan». Variants of the portal vein formation, the angle of inflow of the inferior mesenteric vein into the superior mesenteric and splenic veins, the distance from the point of confluence of the inferior mesenteric vein to the point of confluence with the portal vein were studied. The study revealed that the inferior mesenteric vein in 40% of cases flows into the splenic vein, in 39% - into the angle of confluence of the superior mesenteric and splenic veins, in 16% - into the superior mesenteric vein. In 5% of cases, the absence of the inferior mesenteric vein was revealed. The angle of fusion of the inferior mesenteric vein with the superior mesenteric vein was statistically significantly greater than the angle of fusion of the inferior mesenteric vein with the splenic vein. The angles were 76.36±1.53 ° and 64.89±3.52 °, respectively (p=0.004). The length of the common trunk of the inferior mesenteric and splenic veins was significantly greater than the common trunk of the mesenteric veins and amounted to 16.98±1.09 mm and 9.37±0.65 mm (p 0.001), respectively. Thus, the study showed a high degree of anatomical variability of the inferior mesenteric vein in formation of roots of portal vein of liver.