What determines the degree of difficulty
An extrasphincteric fistula goes around the sphincter and opens into the rectum high above it, often having branched passages and purulent leaks. Degrees from I to IV reflect an increase in complexity: a narrow internal hole without scars and streaks is classified as the first, and a wide hole with a pronounced scarring process, streaks and infiltrates is classified as the fourth. The choice of technique depends on the degree: from one-step excision with suturing to staged treatment with ligation. An accurate assessment before surgery based on ultrasound or MRI data is fundamental here.
What is a perirectal fistula?
A fistula is a pathological canal connecting the rectal cavity to the skin of the perineum. In most cases, it is formed as a result of acute paraproctitis: the abscess has opened, the pus has come out, but the canal remains and periodically becomes inflamed again.
The fistula does not heal on its own: its walls are lined with epithelium and scar tissue. Conservative treatment can only temporarily reduce inflammation, so the only radical method is surgery.
Why are fistulas divided in relation to the sphincter?
- intrasphincteric - passes inside the internal sphincter, the easiest to treat
- transsphincteric - crosses part of the sphincter fibers
- extrasphincteric - bypasses the sphincter from the outside, the most complex, has degrees of complexity I–IV
- epithelial-coccygeal - a separate pathology of the sacrococcygeal region, not associated with the rectum
The main risk of the operation
The key task of the surgeon is to remove the fistula completely and at the same time preserve the function of the anal sphincter. The more sphincter fibers are involved in the fistulous tract, the more complex the operation and the higher the requirements for technology. That is why the volume of intervention and its cost directly depend on the type of fistula.