After food leaves the stomach it enters the small intestine which is made up of 3 parts. The last part is the ileum and when a stoma is formed from here it is called an ileostomy (ile-ostomy)
The large bowel is totally removed, but instead of an ileostomy, an internal Pouch is formed from a section of small bowel.
Officially called the ileoanal reservoir, this procedure is a surgical treatment option for chronic ulcerative colitis, colon cancer and familial polyposis patients who need to have their large intestine (colon) removed. An ileoanal reservoir (or pouch) is an internal pouch formed of small intestine. This pouch provides a storage place for stool in the absence of the large intestine. Anal sphincter muscles assist in holding in the stool. Several times a day, stool is passed through the anus