Ileal pouch: A surgically created chamber made up of a portion of the lower part of the ileum, the last (lowest) part of the small intestine.
The ileal pouch generally connects to the rectum with the muscles of this area left intact (the anus) to allow continuation of bowel control. The ileal pouch acts as a reservoir with the goal being a return to regular bowel habits despite removal of the large intestine.
Surgery to create an ileal pouch is usually done for patients who need a total colectomy (removal of the entire colon or large intestine that part of the intestinal tract normally positioned between the ileum and the rectum). Patients with ulcerative colitis are the most common candidates for an ileal pouch.