Ileocecal valve

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Ileocecal valve
Gray1075.png
Interior of the cecum and lower end of ascending colon, showing colic valve. ("Colic valve" is an older term for the ileocecal valve.)
Ileocecal valve.jpg
Endoscopic image of cecum with arrow pointing to ileocecal valve in foreground.
Latin valva ileocaecalis
Gray's p.1179
Artery ileocolic artery
Vein ileocolic vein
MeSH Ileocecal+valve
Anatomical terminology

The ileocecal valve, or ileocaecal valve, is a papillose structure with physiological sphincter muscle situated at the junction of the small intestine (ileum) and the large intestine, with recent evidence indicating an anatomical sphincter may also be present in humans.[1] Its critical function is to limit the reflux of colonic contents into the ileum.[2]

The ileocecal valve is distinctive because it is the only site in the GI tract which is used for Vitamin B12 and bile acid absorption.[3][4]

Functionally, roughly two litres of fluid enters the colon daily through the ileocecal valve.

Histology[edit]

The histology of the ileocecal valve shows an abrupt change from a villous mucosa pattern of the ileum to a more colonic mucosa. A thickening of the muscularis mucosa[citation needed], which is the smooth muscle tissue found beneath the mucosal layer of the digestive tract. A thickening of the muscularis externa is also noted.[1]

There is also a variable amount of lymphatic tissue found at the valve.[5]

Clinical significance[edit]

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.[6]

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.[7]

Pathology[edit]

Tumors of the ileocecal valve are rare, but have been reported in the literature.[8][9]

Etymology[edit]

It was described by the Dutch physician Nicolaes Tulp (1593–1674), and thus it is sometimes known as Tulp's valve.

Additional images[edit]

References[edit]

  1. ^ a b Pollard, MF; Thompson-Fawcett, MW; Stringer, MD (2012). "The human ileocaecal junction: anatomical evidence of a sphincter". Surgical and Radiologic Anatomy 34 (1): 21–9. doi:10.1007/s00276-011-0865-z. PMID 21863224. 
  2. ^ Barret KE. "Lange Gastrointestinal Physiology". The McGraw-Hill Companies, 2006.
  3. ^ Fornaro, R.; Belcastro, E.; Lo Presti, G.; Carissimi, T.; Ferraris, R. (1991). "The ileocecal valve as a prognostic factor in extensive resection of the small intestine". Chirurgia italiana 43 (1–2): 49–54. PMID 1769094.  edit
  4. ^ Steiner, M. S.; Morton, R. A. (1991). "Nutritional and gastrointestinal complications of the use of bowel segments in the lower urinary tract". The Urologic clinics of North America 18 (4): 743–754. PMID 1949406.  edit
  5. ^ Burkitt HG, Young B, Heath JW. Wheater's Functional Histology: a text and colour atlas. Churchill Livingstone, London, 1993.
  6. ^ Cotton PB, Williams CB. Practical Gastrointestinal Endoscopy Blackwell Publishers, London, 1996
  7. ^ Ross, AS; Waxman, I; Semrad, C; Dye, C (2005). "Balloon-assisted intubation of the ileocecal valve to facilitate retrograde double-balloon enteroscopy". Gastrointestinal endoscopy 62 (6): 987–8. doi:10.1016/j.gie.2005.09.002. PMID 16301054. 
  8. ^ Yörük, G; Aksöz, K; Buyraç, Z; Unsal, B; Nazli, O; Ekinci, N (2004). "Adenocarcinoma of the ileocecal valve: report of a case". The Turkish journal of gastroenterology : the official journal of Turkish Society of Gastroenterology 15 (4): 268–9. PMID 16249985. 
  9. ^ Song, HJ; Ko, BM; Cheon, YK; Ryu, CB; Lee, JS; Lee, MS; Shim, CS (2005). "Isolated ileocecal lymphoma". Gastrointestinal endoscopy 61 (2): 293–4. doi:10.1016/S0016-5107(04)02548-9. PMID 15729248. 

External links[edit]