1. (Science: anatomy) a vessel that directly interconnects an artery and a vein, and that acts as a shunt to bypass the capillary bed. Not to be confused with surgical anastomosis, nor with arteriovenous fistula.
2. (a) The direct or indirect connection of separate parts of a branching system to form a network, especially among blood vessels.
(b) The surgical connection of separate or severed tubular hollow organs to form a continuous channel as between two parts of the intestine.
3. The connection of normally separate parts or spaces so they intercommunicate. An anastomosis may be naturally occurring or artificially constructed and be created during the process of embryonic development or by surgery, trauma or pathological means.
An anastomosis may, for example, connect two blood vessels (as in a naturally occurring arteriovenous anastomosis, a connection between an artery and a vein) or it may connect the healthy sections of the colon or rectum after a cancerous or otherwise diseased portion has been surgically removed. A gastrojejunal anastomosis connects the stomach directly with the jejunum.
The term “anastomosis” comes straight from the Greek. It originally referred to an opening or junction through a mouth as of one body of water with another. Anastomosis has been in medical usage since the Greek physician Galen (129-200 AD) used it to describe the interconnections between blood vessels. The plural is anastomoses.
arteriovenous anastomosis - one between an artery and a vein.
crucial anastomosis - an arterial anastomosis in the upper part of the thigh.
1. one connecting the end of an artery and that of some other vessel. 2. anastomosis of two sections of colon, as with partial colectomy or closure of an ileostomy.
end-to-side anastomosis - an anastomosis connecting the end of one vessel with the side of a larger one.
heterocladic anastomosis - one between branches of different arteries.
homocladic anastomosis - one between two branches of the same artery.
ileoanal pull-through anastomosis - anastomosis of an ileoanal reservoir to the anal canal by means of a short conduit of ileum pulled through the rectal cuff and sutured to the anus, allowing continent elimination of feces following colectomy.
intestinal anastomosis - establishment of a communication between two formerly distant portions of the intestine.
anastomosis of Riolan - anastomosis of the superior and inferior mesenteric arteries.
Roux-en-Y anastomosis - any Y-shaped anastomosis in which the small intestine is included.