Absolutely - it's a last resort effort for issues such as yours and mine. LAST RESORT. My colectomy was in 2004, I started having the fistula (about the same area you have yours, it sounds like,) in 2005 and repairs were started in 2006. After the seton stitch, the attempt to "patch" up the hole with tissue from one side of my vulva (bulbo-cavernosa), and the attempts to use muscle from behind my knee and in my upper thighs to "patch" up the fistula all failed, they decided on the Pouch Advancement. They went in through the original abdominal scar (above the belly button down to pubis) from where the conducted the colectomy. They removed the pouch and disconnected it, cut out the portion of the rectum (small tiny bit) that was affected by the fistula and reconnected. I had another temporary ostomy at that time but my problems with those are a whole other story
. (I'm a doctor's worst nightmare, but you may have an idea of what I mean.) The vaginal side, thankfully, healed almost immediately, though I was still scarred and healing from the initial attempts. It's used as a last resort because most people heal better than I did/do and respond to the other options well. The more you remove from that end where the rectum is left, the less control you have, and less you have to work with in general.