The sigmoid vein, also called the vena sigmoideus, refers to one group of sigmoid veins. These veins are tributaries of the inferior mesenteric vein, which is a tributary of the hepatic portal vein.

The sigmoid sinus is a dural venous sinus that lies deep within the human head, and just below the brain. A dural sinus is a channel that lies between the dura mater, the outermost tissue covering the ...