Ileocolic artery

At a glance

English

Ileocolic artery

Latin (TA2)

Arteria ileocolica

System

Artery

Region

Trunk

Side

Single, on the midline

About the ileocolic artery

The ileocolic artery is the lowest of the branches that leave the right side of the superior mesenteric artery. It runs downwards and to the right, behind the peritoneum of the posterior abdominal wall, towards the right iliac fossa, where the small intestine opens into the large intestine at the ileocaecal junction. On its way it passes in front of the right ureter and the right psoas major.

Close to the junction it divides into several branches. An ascending (colic) branch runs up beside the ascending colon to join the right colic artery, or the middle colic when no right colic is present. Anterior and posterior caecal arteries pass to the front and back of the caecum. An ileal branch turns to the left along the terminal ileum and links with the end of the superior mesenteric artery itself. The appendicular artery, usually from one of the lower branches, runs behind the terminal ileum and then along the free edge of the mesoappendix to the tip of the appendix.

These branches feed into the marginal artery at the start of the colon and make the ileocaecal region one of the better supplied parts of the gut.

The ileocolic artery is the key vessel in right hemicolectomy. It is divided close to its origin so that the lymph nodes that lie along it can be removed with the bowel. In appendicectomy the appendicular artery is tied in the mesoappendix; because it is an end artery, blocking it in appendicitis can leave the appendix wall short of blood and prone to perforation.

Course and supply

Arises from

The right side of the superior mesenteric artery, as its lowest colic branch.

Ends in

Ends near the ileocaecal junction in ascending, caecal, appendicular and ileal branches.

Supplies

Supplies the terminal ileum, the caecum, the appendix and the first part of the ascending colon.