Fistula Surgery
An anal fistula — also called fistula-in-ano — is a tunnel that develops between the
inside of the anus and the outside
skin around the anus. The anus is the muscular opening at the end of the digestive tract
where stool exits the body.
Most anal fistulas are the result of an infection that starts in an anal gland. The
infection causes an abscess that
drains on its own or is drained surgically through the skin next to the anus. This
drainage tunnel remains open and
connects the infected anal gland or the anal canal to a hole in the outside skin around
the anus.
Surgery is usually needed to treat an anal fistula. Sometimes nonsurgical treatments may
be an option.