Mr Mike Williamson

Consultant General and Colorectal Surgeon

Circle Bath Hospital

01761 422 222

Anal Fistula

An anal fistula is an abnormal tunnel between the inside of your anus and the skin outside the anus. They are usually the result of a pus-filled cavity (known as an abscess) which has formed by chance in the nearby tissue. When the pus drains, it leaves behind a narrow tunnel joining the “internal opening” in the anal canal to the “external opening” on the skin. This tunnel always passes through some anal sphincter muscle on the way.

Once an anal fistula has formed, the body won't then heal and repair it naturally. If an anal fistula is left untreated it may cause further abscesses and worsening fistulas in the future. For this reason, I always advise getting expert help and treatment for an anal fistula; it really can help prevent further problems occurring.

Anal fistulas are treated by surgery and there are a variety of ways this can be carried out. The exact type of surgery done will depend on the nature, size and location of your fistula.

One of the most common operations, done for simple fistulas (called “low fistulas” because they only affect the lower part of the anal muscle) is known as a fistulotomy. This involves cutting open the fistula with overlying skin and muscle along its entire length (a process known as "laying open") so that it heals over time into a flat scar.

This is usually a successful operation with a fast recovery. People often find they are able to use the toilet without pain or discomfort after just a few days. It is done as a day case, meaning people are able to go home later the same day.

Unfortunately, some fistulas involve more of the anal muscle, sometimes over half of it, and these are called “high fistulas”. As you would expect, this makes surgery more difficult and complex, because if I cut those types of fistula open, I would be cutting a significant part of the anal muscle as well, which could make the person incontinent.

There are a range of techniques to deal with these more complex “high” fistulas, with new ones being developed all the time. The aim is to avoid damaging the muscle or causing continence problems. A brief overview of a few of these techniques can be seen below:

  • Surgical thread, called a Seton, is placed in the fistula to keep it open, giving it time to drain and avoid new abscesses forming. This is usually a temporary measure to prepare patients for complex surgery.
  • Advancement flap procedure involves cutting or scraping out the fistula and covering the internal opening in the anal canal with tissue taken from inside the rectum.
  • A bioprosthetic plug using animal collagen is inserted to block the whole track of the fistula. This is losing popularity because of its high failure rate.
  • Ligation of the intersphincteric fistula tract (LIFT): an incision is made in the skin over that part of the anal sphincter involved by the fistula and then the sphincter muscles are separated until the fistula track is identified and then it is tied off.
  • Core fistulectomy: involves tunnelling out the fistula track along its full length to remove the fistula but avoid cutting too much muscle.

I appreciate that it can be confusing, and even overwhelming, to see the sheer number of options available. This is where experience is so important. I have been treating fistulas for over 20 years and strongly believe in providing a tailored approach to care and treatment, one that meets the needs of the individual to give the best possible benefits.

I don't take on new techniques without long consideration and looking at all the evidence. I will only ever adopt a technique when it has shown to be beneficial without undue additional risks.

Many of the people who come to see me have often read about new treatments, or new trials of treatments, and I am always very happy to talk about these with them and give them my perspective based on many years of working in this field.

Your recovery will depend on the type of operation you have, but it is usually fairly quick. You will have a sore bottom for a while but not that sore, and you should be able to carry on with everyday activities fairly quickly afterwards.

I'll see you again about two weeks after your surgery, to check the wound is healing correctly. This is really important for anal fistulas as we want to make sure the wound doesn't heal back into a fistula again.

In the 20+ years I have been working as a consultant colorectal surgeon, I have treated many people who were struggling with an anal fistula. I have seen the difference that the correct treatment can make to the quality of their lives. Being able to get them out of pain and back to normal again is incredibly rewarding.

If you would appreciate help and advice, it is very easy to book a consultation with me. Please contact my private secretary who will be delighted to schedule things for a time that is most convenient for you.

Fast track your treatment with Mike Williamson

Just enter your details below and we'll contact you to book a convenient time for a consultation (whether you're paying for yourself or are insured).

We will use your personal information to process and respond to your enquiry and contact you with relevant information. For further information, please see our website privacy policy.

Fast track your treatment

Just enter your details below and we'll ring you to provide a quote or answer your questions. We will use your personal information to process your enquiry and contact you with relevant information. For further information, please see our website privacy policy.

020 3613 6779

Circle Bath Hospital, Foxcote Avenue, Peasedown St John, Bath BA2 8SQ


Overall rating 24th April 2017