CT Anatomy Tutorials:
The Inferior Mesenteric Vein




Red=inferior mesenteric vein

Yellow=superior rectal vein

Orange=left colic artery

Green=superior rectal artery

Blue=Left colic vein

Black=inferior mesenteric artery




Axial CT sections from the aortic bifurcation to the origin of the inferior mesenteric artery

The superior rectal vein and artery are shown in the first image on the left. As they are followed superiorly, the inferior mesenteric artery in the second image is shown bifurcating into its two terminal branches, the superior rectal artery and the left colic artery. The two veins that converge to form the inferior mesenteric vein, the superior rectal vein and the left colic vein, are also indicated in this image. The image on the right shows the inferior mesenteric vein in the mid abdomen at the level of the inferior poles of the kidneys.


Red=inferior mesenteric vein

Yellow=fourth portion of the duodenum

Green=left renal vein

Blue=jejunum at the ligament of Treitz




Axial CT sections from the mid abdomen below and at the ligament of Treitz

Finding the inferior mesenteric vein in the midabdomen is often difficult because it lies adjacent to several other vessels such as the ovarian/testicular artery and veins and the left colic artery and veins. As shown in these images, the inferior mesenteric vein is the only vessel that continues superiorly anterior to the left renal vein. Above the left renal vein, the inferior mesenteric vein lies in or adjacent to the ligament of Treitz, forming a readily identifiable marker for the junction between the fourth portion of the duodenum and the jejunum.

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