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.