The operation is usually performed under a general anaesthetic and usually takes 15 to 30 minutes.
To lessen the risk of bowel incontinence (when you pass a bowel movement without wanting to) your treatment may involve several operations over a number of months.
The type of surgery you need will depend on where the fistula is (see figure 1).
•If the fistula is below or crosses the lower part of the sphincter muscles, your surgeon will cut the fistula open to your skin and leave the wound open so that it can heal with healthy tissue.
•If the fistula has branches that pass through the upper part of the sphincter muscles, your surgeon may place a special stitch (called a seton stitch) in the fistula to allow pus to drain easily.
•The fistula may be suitable for treatment with a plug made from pig-bowel tissue. Your surgeon will not need to make a cut in the sphincter muscle.
•If the fistula reaches above your sphincter muscles, you may need to have a temporary colostomy (your large bowel opening onto your skin). However, this is not common.