Ileocecal valve
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Ileocecal valve | |
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Interior of the cecum and lower end of ascending colon, showing colic valve. ("Colic valve" is an older term for the ileocecal valve.) | |
Endoscopic image of cecum with arrow pointing to ileocecal valve in foreground. | |
Latin | valva ileocaecalis |
Gray's | subject #249 1179 |
Artery | ileocolic artery |
Vein | ileocolic vein |
MeSH | Ileocecal+valve |
Dorlands/Elsevier | v_02/12843921 |
The ileocecal valve is situated at the junction of the small intestine (ileum) and the large intestine. It regulates the flow of chyme into the bowels.
Functionally, roughly two litres of fluid enters the colon daily through the ileocecal valve.
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[edit] Histology
The histology of the ileocecal valve shows an abrupt change in the villous pattern which is found in small intestinal mucosa, to the glandular pattern found in colonic mucosa.
At the ileocecal valve, there is also thickening of the muscularis mucosa, which is the smooth muscle tissue found beneath the mucosal layer of the digestive tract.
There is also a variable amount of lymphatic tissue found at the valve.[1]
[edit] Clinical significance
During colonoscopy, the ileocecal valve is used, along with the appendiceal orifice, in the identification of the cecum. This is important, as it indicates that a complete colonoscopy has been performed. The ileocecal valve is typically located on the last fold before entry into the cecum, and can be located from the direction of curvature of the appendiceal orifice, in what is known as the bow and arrow sign.[2]
Intubation of the ileocecal valve is typically performed in colonoscopy to evaluate the distal, or lowest part of the ileum. Small bowel endoscopy can also be performed by double-balloon enteroscopy through intubation of the ileocecal valve.[3]
[edit] Pathology
Tumours of the ileocecal valve are rare, but have been reported in the literature.[4][5]
[edit] Etymology
It was discovered by the Dutch physician Nicolaes Tulp (1593-1674), and thus it is sometimes known as Tulp's valve.
[edit] References
- ^ Burkitt HG, Young B, Heath JW. Wheater's Functional Histology: a text and colour atlas. Churchill Livingstone, London, 1993.
- ^ Cotton PB, Williams CB. Practical Gastrointestinal Endoscopy Blackwell Publishers, London, 1996
- ^ Ross AS, Waxman I, Semrad C, Dye C. Balloon-assisted intubation of the ileocecal valve to facilitate retrograde double-balloon enteroscopy. Gastrointest Endosc. 2005 Dec;62(6):987-8. PMID 16301054
- ^ Yoruk G, Aksoz K, Buyrac Z, Unsal B, Nazli O, Ekinci N. Adenocarcinoma of the ileocecal valve: report of a case. Turk J Gastroenterol. 2004 Dec;15(4):268-9. PMID 16249985
- ^ Song HJ, Ko BM, Cheon YK, Ryu CB, Lee JS, Lee MS, Shim CS. Isolated ileocecal lymphoma. Gastrointest Endosc. 2005 Feb;61(2):293-4. PMID 15729248
[edit] External links
Anatomy of torso, digestive system: Gastrointestinal tract |
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Upper gastrointestinal tract Mouth • Pharynx (nasopharynx, oropharynx, hypopharynx) • Esophagus • Crop • Stomach (rugae, gastric pits, cardia/gland, fundus/gland, pylorus/gland, pyloric antrum) Lower gastrointestinal tract Large intestine: Cecum • Colon (ascending colon, transverse colon, descending colon, sigmoid colon) • Rectum (Houston valve, rectal ampulla, pectinate line) • Anal canal (anal valves, anal sinuses, anal columns) Anus: Sphincter ani internus muscle • Sphincter ani externus muscle GALT: Peyer's patches • M cells intestinal villus • crypts of Lieberkühn • circular folds • taenia coli • haustra • epiploic appendix |