Origin of the porta vein: anatomy study

Abstract

Introduction: classically the portal vein originates from the confluence of the superior mesenteric vein and splenic mesenteric trunk, last one conformed by the splenic and inferior mesenteric veins. Its conformation and main tributaries does not escape from presenting anatomical variations, which the surgeon must know and anticipate, at the time of approaching the pancreatic duodenum massif in order to avoid catastrophic consequences. The objective is the study of the conformation, dimensions and spatial arrangement of the origin of the portal vein, and its main tributaries. Materials and method: 50 cadavers were. Portal vein origin, caliber and its tributaries were recorded. Flaring angles and vertebral projection level. Results: three types of origin were distinguished. Type I was recorded in 78% of cases, type II in 18% and type III in 4%. The calibers were: portal vein 16.12 mm, superior mesenteric 11.77 mm, splenic 9.34 mm, inferior mesenteric 5.03 mm and splenomesaraic trunk 10.44 mm. The latter reached a length of 20.26 mm. The angles were: portal angle - splenomesenteric trunk 124.18 °, upper mesenteric angle - splenomesenteric trunk 101.92 ° and lower mesenteric angle - splenic 75.4 °. In 75% of cases the level of vertebral projection was the upper third of L2. Conclusions: the most frequent origin was according to the classically described. About variants, the meeting of the superior mesenteric vein with the splenic vein is more constant, being the termination of inferior mesenteric vein more variable.