Fistula in Ano or Anal Fistula is caused by abnormal communication between the epithelialized surface of the anal canal and the skin surrounding the anus. Anal Fistulae originate from the anal glands which are located in between the internal and the external anal sphincter. They drain further into the anal canal. Blockage of the outlets of the anal glands leads to the formation of an abscess which eventually can extend to the surface of the skin. The tract thus formed is called a fistula. If the fistula seals over, pus can accumulate and abscesses can re-occur. It is an extremely perplexing disease.
Types of Anal Fistula or Fistula of Ano –
- Extrasphincteric Fistulae – This type of fistula of ano begins at the rectum and moves downwards through the levator ani muscle further opening into the skin that surrounds the anus.
- Suprasphincteric Fistulae – This type occurs between the internal and external sphincter muscles and extend downwards beyond the puborectalis muscle and the levator ani muscles. They open an inch or more away from the anus.
- Transphicteric Fistulae – They occur behind the anus and extend beyond the external sphincter muscle opening into the skin spaced an inch or so away from the anus. At times, transphincteric fistulae grow in a ‘U’ shape forming multiple openings in the skin around the anus. In medical terms, this formation is called a ‘Horseshoe Fistula’.
- Intersphincteris Fistulae – This type of fistula of ano passes through the internal sphincter muscle and extends beyond external sphincter muscles before it opens in the skin around the anus. They usually open very close to the anus.
- Submucosal Fistulae – These are superficial fistulae that pass beneath the submucosa without crossing the internal or the external sphincter muscles.
Symptoms of Anal Fistula or Fistula in Ano –
- Irritation, itching or pain in the affected area.
- Discomfort and inconvenience in the affected area.
- Maceration of skin at the affected area around the anus.
- Draining of pus or blood. Some rare cases reported passing of feces through the fistula.
- Tenderness and swelling along with fever.
- Unpleasant odor from the affected area.
Causes of Anal Fistula or Fistula in Ano –
- Infection due to recurrent abscesses.
- Inflammatory bowel diseases like Crohn’s disease.
Diagnosis of Fistula of Ano –
- Fistula Probe – A narrow instrument called a fistula probe is used to examine the fistulae. Examination can help detect and confirm the condition. Depending on the severity, the examination may be carried out in an outpatient setting or under anaesthesia.
- Anoscopy – An anoscopy is carried out with the help of a small, tubular instrument called an anoscope. An anoscope allows the doctor to examine the internal sections of the anal canal to confirm presence of fistula.
- Sigmoidoscopy – A sigmoidoscopy is performed with the help of a flexible fiber optic tube by inserting the tube into the rectum. This procedure helps examine the lower part of the large intestine.
- Imaging techniques – Imaging techniques like magnetic resonance imaging (MRI) can be used to to assess the anatomy of the fistula.
Treatment of Anal Fistula –
Minimally Invasive Anal Fistula Treatment (MAFT) Surgical procedure is carried out under general or spinal anaesthesia and involves utilizing the external opening of the fistula. Hi and complex fistulae can be managed without damaging the sphincter thus maintaining control over defecation.
Fistuloscope having various channels is inserted through the external opening to visualize the fistula tract and to localize the internal opening. A solution made of glycine mannitol (also known as irrigation solution) is then allowed to inflate and define the fistula track. This further helps localizing the internal opening of the fistula track by gently advancing the fistuloscope through the track.
Once the internal opening has been located, the Surgeon sutures the opening. The surgeon then examines the entire track for secondary fistulae or abscess cavities. In case of presence of abscess cavities and secondary fistulae, they are drained and a fulguration is performed with the help of a flexible mono-polar electrode. The damaged tissue is removed with the help of an endobrush that is passed through the fistuloscope. Internal opening is then disconnected by firing a stapler. A temporary dressing is then applied at the external opening. Patient usually gets discharged the next day and may resume work in 2 - 3 days without any need of repeated dressings.
Dr. Nikhil Agnihotri, expert Laparoscopic Surgeon provides Anal Fistula Treatment in New Delhi with MAFT Surgery in Delhi, India. Contact us to know more about treatment and cost.