Ileo-anal pouch

In medicine, the ileal pouch-anal anastomosis (IPAA), also known as an ileo-anal pouch, restorative proctocolectomy, ileal-anal pullthrough, or sometimes referred to as a j-pouch, s-pouch, w-pouch or an internal pouch (or Kock pouch), is a surgically constructed internal reservoir; usually situated near where the rectum would normally be. It is formed by folding loops of small intestine (the ileum) back on themselves and stitching or stapling them together. The internal walls are then removed thus forming a reservoir. The reservoir is then stitched or stapled into the perineum where the rectum was. The procedure retains or restores functionality of the anus with stools passed under voluntary control of the patient.

Ileo-anal pouches are constructed for people who have had their large intestine surgically removed due to disease or injury. Diseases and conditions of the large intestine which may require surgical removal include:

There is debate about whether patients suffering from Crohn's disease are suitable candidates for an ileo-anal pouch due to the risk of the disease occurring in the pouch, which could make matters even worse. An alternative to an ileo-anal pouch is an ileostomy.

Ulcerative colitis is cured if the large intestine is removed and the patient has the pouch created, but Crohn's disease often inflames the pouch and the adjacent small intestine after this surgery is performed. When this happens, it can result in the return of symptoms and dysfunction of the pouch.

In some cases where the pouch was formed to manage colitis, inflammation can return to the pouch in a similar way to the original inflammation in the colon. This is known as pouchitis.

The surgical procedure for forming an ileo-anal pouch (jpouch) was pioneered by Sir Alan Parks at St. Mark's Hospital in London in the mid to late 1970s and details of the procedure were first published in the British Medical Journal in 1978. The pouch was also known as a Parks' Pouch but more commonly is referred to as a 'Jpouch'. The Jpouch was developed as an alternative to the ileostomy. An ileostomy is where, in the absence of the colon, the small intestine is brought through the abdomen and sewn down forming an opening called a stoma. The stomal opening is where incontinent intestinal waste is emptied into a bag worn by the patient.

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Wikipedia