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]]