In general surgery, a Roux-en-Y anastomosis, less formally and precisely Roux-en-Y, is a surgically created (end-to-side) anastomosis. Typically, it is between small bowel and small bowel that is distal (or further down the gastrointestinal tract) from the cut end.
The name is derived from the surgeon who first described it (César Roux) and the stick-figure representation. Diagramatically, the Roux-en-Y anastomosis looks like the letter Y; typically, the two upper limbs of the Y represent (1) the proximal segment of stomach and the distal small bowel it joins with and (2) the blind end that is surgically divided off, and the lower part of the Y is formed by the distal small bowel beyond the anastomosis.
Roux-en-Ys are used in several operations and collectively called Roux operations.
Operations that make use of a Roux-en-Y
- Some gastric bypasses for obesity.
- Roux-en-Y reconstruction following partial or complete gastrectomy for stomach cancer.
- Roux-en-Y hepaticojejunostomy used to treat (macroscopic) bile duct obstruction which may arise due to:
- Roux-en-Y choledochojejunostomy - indications same as Roux-en-Y hepaticojejunostomy.
- Roux-en-Y pancreas transplant 
- Roux-en-Y pancreas reconstruction after blunt abdominal trauma.
- Roux operation. whonamedit.com. http://www.whonamedit.com/synd.cfm/3724.html. Accessed on: February 7, 2008.
- Surgery to remove stomach cancer. cancerhelp.org.uk. URL: http://www.cancerhelp.org.uk/help/default.asp?page=3917. Accessed on: February 7, 2008.
- Lawrence PF. Essentials of general surgery. 3rd Ed. Lippincott Williams & Wilkins. 2000. ISBN 0-683-30133-0.
- Template:Cite doi/10.1016.2Fj.ciresp.2011.07.018
- Anastomoses - thefreedictionary.com.