Expected headings
"Origin and course"
"The inferior mesenteric vein drains the mesenteric arcade of the hindgut (comprising of distal transverse, descending, and sigmoid colon). Specifically, it drains the tributaries of sigmoid veins, middle and left colic veins, as well as the superior rectal vein. The rectal vein and sigmoid vein usually join to form a common trunk before uniting with the left colic vein."
"The inferior mesenteric vein usually drains into the splenic vein; however, anatomical variants where it drains to the superior mesenteric vein or at the splenoportal angle are not uncommon."