Superior mesenteric vein

In human anatomy, the superior mesenteric vein is a blood vessel that drains blood from the small intestine. Behind the neck of the pancreas, the superior mesenteric vein combines with the splenic vein to form the portal vein that carries blood to the liver. The superior mesenteric vein lies to the right of the similarly named artery, the superior mesenteric artery, which originates from the abdominal aorta.

Structure

Tributaries of the superior mesenteric vein drain the small intestine, large intestine, stomach, pancreas and appendix and include:

Right gastro-omental vein
inferior pancreaticoduodenal veins
veins from jejunum
veins from ileum
middle colic vein – drains the transverse colon
right colic vein – drains the ascending colon
ileocolic vein

The superior mesenteric vein combines with the splenic vein to form the portal vein.

Clinical significance

Thrombosis of the superior mesenteric vein is quite rare, but a significant cause of mesenteric ischemia and can be fatal. It is estimated that 10–15% of mesenteric ischemia is due to mesenteric thrombosis.