What is an ileoanal reservoir?

An ileoanal reservoir is a pouch that is constructed from the small intestines, specifically a segment of the ileum. This surgical procedure, often referred to as an ileoanal pull-through or J-pouch surgery, is typically performed for patients who have undergone a colectomy due to conditions like ulcerative colitis or familial adenomatous polyposis. The ileoanal reservoir allows for the storage and passage of stool, mimicking the function of a normal rectum, thus enabling patients to maintain a more natural bowel function and reducing the need for an external ostomy bag.

The other options describe components or processes that are not associated with the ileoanal reservoir: a pouch created from the colon involves the large intestine, which is not applicable here as the reservoir relies on the ileum; a surgical incision into the abdomen is part of the surgical process but does not define what the ileoanal reservoir is; and a type of ostomy procedure generally refers to a diversion of waste through an opening in the abdomen, while the ileoanal reservoir aims to restore continuity of the intestinal tract.