Anal Fistula Surgery

Anal Fistula Surgery

Anal Fistula Surgery

I specialise in the treatment of complex fistulae.  I am a Consultant General Surgeon and Colorectal Lead at Mid Cheshire Hospital, Consultant Surgeon at BMI Alexandra Hospital and South Cheshire Private Hospital.  I am also the Lead Consultant for Enhance Recovery Programme in Colorectal Surgery and Colorectal Multi Disciplinary Team.  My practice includes diagnosis and treatment of complex fistula in ano, colovesical fistula, coloveginal fistula, enterocutaneous fistula and fistulae caused by Chrohn’s disease.

Anal Fistula

An anal fistula is when a small, tunnel like structure (tract) develops between the back passage (anal canal) and the opening to the outer skin surrounding the anus. There are many different types of fistula, ranging from a simple to more complicated fistulas which can be made up of several tracts which branch out.  An anal fistula usually develops after an anal abscess arising in the anal crypts. It can also form an incompletely treated abscess. They can also be caused by a condition which affects the intestines, such as irritable syndrome or Crohn’s disease or trauma to ano-rectum.


The symptoms of an anal fistula may include throbbing pain, irritation of skin around the anus, fever, pus discharge, fever, abdominal pain, diarrhoea, nausea and vomiting.


Anal fistulas most commonly develop as a result of an anal abscess.  An anal abscess normally develops after a small gland, just inside the anus, becomes infected with bacteria or foreign matter. Abscesses are usually treated with a course of antibiotics. In most cases, you will also need to have the infected fluid drained away from the abscess.  If an anal abscess bursts before it has been treated, then it can sometimes lead to an anal fistula.

Anal fistulas are also a common complication of conditions that result in inflammation of the intestines. Some of these conditions include, irritable bowel syndrome (IBS), diverticulitis, ulcerative colitis, Crohn’s disease, tuberculosis and cancer of the rectum.


To make a diagnosis, your GP will look at your medical history and carry out a physical examination. Your GP inquire about any history of anal abscesses or conditions which affect your bowels, such as Crohn’s disease, as these conditions can sometimes lead to an anal fistula.  Your GP will inspect your anal region to see if there are physical signs of a fistula. The opening of a fistula normally appears as a red, inflamed spot, which is often oozing pus. After diagnosis

Investigations by your Specialist

After your physical examination you may need proctoscopy, sigmoidoscopy or camera examination of large bowel and rectum. You may also require examination under anaesthetic (EUA) for further assessment of fistula.

Proctoscopy or Anoscopy   

This instrument is lubricated and is passed a few inches into your rectum. An anoscope has a light on the end, which allows the person using it to see the entire anal canal. It is also able to take small tissue samples (biopsy).


this involves having a special solution injected into your fistula. You will then have an x-ray, which shows the path taken by the fistula.

Magnetic resonance imaging (MRI)

Scan  this scan uses magnetic and radio waves to produce detailed images of the inside of your body.  The test is safe and does not involve radiation. It is contraindicated in patients with cardiac pace makers.


Very few anal fistulas are able to heal by themselves, so surgery is usually necessary.  The main aim of treatment for an anal fistula is to heal the fistula with as little effect on the anal sphincter muscles (the ring of muscles that open and close the anus) as possible. Damage to the sphincter muscles could cause transient incontinence problems in the future in rare cases incontinence may be permanent.


The main surgical procedure used to treat a fistula is a fistulotomy. During this procedure, the surgeon will cut open the fistula, whilst you are under general anaesthetic, and then scrape and flush out its contents. The fistula is then laid open and flattened out. After 1-2 months, the fistula will heal into a flat scar. To access the fistula, your surgeon may have to cut a small portion of the anal sphincter muscle.  Fistulectomy patients may be discharged on the same day or may require admission for a few days depending on complexity of fistula surgery.  Some patients may require a second stage procedure.

It can be painful to move around soon after the operation, but after approximately one week, any pain and discomfort should ease. Most people make a full recovery after two to six weeks, but if the fistula was particularly complicated, it can take up to year for it to heal completely.

Fibrin glue or collagen plug

This is a new technique and the results are unpredictable.  Most cases of anal fistula will require surgery, however, in some cases you may be able to have the fistula sealed with a special type of glue made from protein. This means the fistula will not have to be cut open. The glue is injected through the opening of the fistula, and then stitched closed. A fistula can also be sealed using a small plug made of collagen and then stitched closed

Treatment with Seton

Seton is a safe and effective way of treating complex anal fistulae.  This involves a general anaesthetic and insertion of a thin tube or suture through a fistula tract and tieing the ends together outside of the body. The seton is replaced or tightened overtime, gradually cutting through the sphincter muscle and goes healing as it goes.  This option minimise scarring but can cause incontinence in a small number of cases. The seton can remain in place until the fistula is completely cured. The process my sometimes involve 1-5 procedures and may take from two months to a year to cure the problem.  Anal fistula can recur after primary treatment.