Inferior mesenteric artery 2332113 213991711 2008-05-21T17:50:30Z 24.39.54.150 add Gray537 to gallery {{Infobox Artery | Name = {{PAGENAME}} | Latin = arteria mesenterica inferior | GraySubject = 154 | GrayPage = 609 | Image = Gray538.png | Caption = [[Sigmoid colon]] and [[rectum]], showing distribution of branches of [[inferior mesenteric artery]] and their [[anastomoses]]. (Inferior mesenteric artery labeled at center.) | Image2 = gray985.png | Caption2 = Abdominal part of digestive tube and its attachment to the primitive or common mesentery. Human embryo of six weeks. (Inferior mesenteric artery labeled at bottom right.) | BranchFrom = [[abdominal aorta]] | BranchTo = [[left colic artery]], [[Sigmoid arteries|sigmoid branches]], [[superior rectal artery]] | Vein = [[inferior mesenteric vein]] | Precursor = [[vitelline arteries]] | Supplies = | MeshName = Mesenteric+Artery,+Inferior | MeshNumber = A07.231.114.565.510 | DorlandsPre = a_61 | DorlandsSuf = 12155065 | }} In [[human anatomy]], the '''inferior mesenteric artery''', often abbreviated as '''IMA''', supplies the [[large intestine]] from the [[Colic flexure|left colic (or splenic) flexure]] to the upper part of the [[rectum]], which includes the [[descending colon]], the [[sigmoid colon]], and part of the rectum. Proximally, its territory of distribution overlaps (forms a watershed) with the [[middle colic artery]], and therefore the superior mesenteric artery. The SMA and IMA anastomose via the [[marginal artery]] (artery of Drummond). The territory of distribution of the IMA is more or less equivalent to the embryonic [[hindgut]]. ==Branching== The IMA branches off the anterior surface of the [[abdominal aorta]] below the [[renal artery]] branch points, and approximately midway between these and the aortic [[bifurcation]] (into the [[common iliac arteries]]). The IMA has the following branches: {| class="wikitable" | '''Branch''' || '''notes''' |- | [[left colic artery]] || supplies [[descending colon]] |- | [[Sigmoid arteries|sigmoid branches]] || the most superior being described as 'the superior sigmoid artery' |- | [[superior rectal artery]]|| effectively the terminal branch of the IMA (the continuation of the IMA after all other branches) |} All these arterial branches further divide into [[Arterial arcades|arcades]] which then supply the [[Colon (anatomy)|colon]] at regular intervals. ==Associated veins== The IMA is accompanied along its course by a similarly named [[vein]], the [[inferior mesenteric vein]], which drains into the [[splenic vein]]. The IMV therefore drains to the [[portal vein]] and does not fully mirror the course of the IMA. ==Surgery and pathology== The IMA and/or its branches must be resected for a left hemicolectomy. A [[horseshoe kidney]], a rare (1 in 600) anomaly of the kidneys, will be positioned below the IMA. ==Additional images== <gallery> Image:Gray531.png|The abdominal aorta and its branches. Image:Gray537.png|The inferior mesenteric artery and its branches. Image:Gray847.png|Abdominal portion of the sympathetic trunk, with the celiac plexus and hypogastric plexus. Image:Gray1042.png|Duodenojejunal fossa. Image:Gray1121.png|Posterior abdominal wall, after removal of the peritoneum, showing kidneys, suprarenal capsules, and great vessels. Image:Gray1227.png|Front of abdomen, showing surface markings for arteries and inguinal canal. </gallery> ==External links== * {{SUNYAnatomyFigs|39|02|05}} - "Branches of the inferior mesenteric artery." * {{SUNYAnatomyLabs|40|11|01|03}} - "Posterior Abdominal Wall: Branches of the Abdominal Aorta" * {{SUNYAnatomyImage|7|9|24}} * {{SUNYAnatomyImage|7|9|97}} * {{SUNYAnatomyImage|8|4|07}} * {{SUNYAnatomyImage|8|6|59}} * {{UMichAtlas|abdo_wall70}} - "Posterior Abdominal Wall, Dissection, Anterior View" * {{NormanAnatomy|sup&infmesentericart}} {{Arteries of thorax and abdomen}} [[Category:Arteries]] [[Category:Abdomen]] [[de:Arteria mesenterica inferior]] [[la:Arteria mesenterica inferior]] [[pt:Artéria mesentérica inferior]] [[fr:Artère mésentérique inférieure]]