The left colic artery is a branch of the

inferior mesenteric artery In human anatomy, the inferior mesenteric artery, often abbreviated as IMA, is the third main branch of the abdominal aorta and arises at the level of L3, supplying the large intestine from the distal transverse colon to the upper part of the ana ...

distributed to the

descending colon In the anatomy of humans and homologous primates, the descending colon is the part of the colon extending from the left colic flexure to the level of the iliac crest (whereupon it transitions into the sigmoid colon). The function of the descendin ...

, and left part of the

transverse colon In human anatomy, the transverse colon is the longest and most movable part of the colon. Anatomical position It crosses the abdomen from the ascending colon at the right colic flexure (hepatic flexure) with a downward convexity to the descend ...

. It ends by dividing into an ascending branch and a descending branch; the terminal branches of the two branches go on to form anastomoses with the

middle colic artery The middle colic artery is an artery of the abdomen; a branch of the superior mesenteric artery distributed to parts of the ascending and transverse colon. It usually divides into two terminal branches - a left one and a right one - which go on ...

, and a

sigmoid artery The sigmoid arteries are 2-5 branches of the inferior mesenteric artery that are distributed to the distal descending colon and the sigmoid colon. Anatomy Course and relations The sigmoid arteries course obliquely inferior-ward and to the lef ...

(respectively).

Structure

The left colic artery usually represents the dominant arterial supply to the

left colic flexure In the anatomy of the human digestive tract, there are two colic flexures, or curvatures in the transverse colon. The right colic flexure is also known as the hepatic flexure, and the left colic flexure is also known as the splenic flexure. Note ...

Course

The left colic artery passes to the left posterior to the

peritoneum The peritoneum is the serous membrane forming the lining of the abdominal cavity or coelom in amniotes and some invertebrates, such as annelids. It covers most of the intra-abdominal (or coelomic) organs, and is composed of a layer of mesoth ...

. After a short but variable course, it divides into an ascending branch and a descending branch.

Branches and anastomoses

Ascending branch

The ascending branch passes superior-ward. It passes anterior to the (ipsilateral) psoas major muscle, gonadal vessels,

ureter The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In a human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epit ...

, and

kidney The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blood ...

; it passes posterior to the

inferior mesenteric vein In human anatomy, the inferior mesenteric vein (IMV) is a blood vessel that drains blood from the large intestine. It usually terminates when reaching the splenic vein, which goes on to form the portal vein with the superior mesenteric vein (SMV) ...

. Its terminal branches form anastomoses with those of the

; it also forms anastomoses with the descending branch (of the left colic artery).

Descending branch

The descending branch passes inferolaterally. It forms anastomoses with the superior-most

as well as the ascending branch (of the left colic artery), thereby participating in the formation of the

marginal artery of the colon In human anatomy, the marginal artery of the colon, also known as the marginal artery of Drummond, the artery of Drummond, and simply as the marginal artery, is an artery that connects the inferior mesenteric artery with the superior mesenteric ar ...

Variation

The left colic artery may have a common origin with a

, or may arise by branching of from a sigmoid artery. Occasionally, the left colic artery may arise from either the superior mesenteric artery, the

, or the proximal-most jejunal artery; rarely, an accessory left colic artery may arise from the aforementioned arteries. An accessory left colic artery may also arise from the left colic artery itself.

Clinical significance

The left colic artery may be ligated during

abdominal surgery The term abdominal surgery broadly covers Surgery, surgical procedures that involve opening the abdomen (laparotomy). Surgery of each abdominal organ is dealt with separately in connection with the description of that organ (see stomach, kidney, l ...

to remove

colorectal cancer Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the colon or rectum (parts of the large intestine). Signs and symptoms may include blood in the stool, a change in bowel m ...

. This may have poorer outcomes than preserving the artery.

Additional images

File:Gray1041.png, Superior and inferior duodenal fossæ. File:Gray1042.png, Duodenojejunal fossa.

References

External links

Lotti M. Anatomy in relation to left colectomy
* * - "Intestines and Pancreas: Branches of the Inferior Mesenteric Artery" * * Arteries of the abdomen {{circulatory-stub pt:Artéria cólica direita