What is an anal fissure?
An anal fissure is a crack in the lining of the anal canal (the bottom of the back passage). This can occur at any age, but usually occurs in young adults. Fissures may be caused by constipation and passage of hard stool, or diarrhoea and passage of frequent stool. However, the majority seem to develop without any particular cause.
The symptoms of a fissure are pain, especially when passing a bowel motion, and some bleeding. Occasionally, people experience discharge of abscesses in association with a fissure.
Anal fissures may be acute (recent onset) or chronic (present for a long time or recurring frequently). An acute fissure is usually due to altered bowel habits, while a chronic fissure may be due to poor bowel habits, overly tight or spastic anal sphincter muscles, scarring or an underlying medical problem.
How can a fissure be treated?
At least 50 per cent of fissures heal either by themselves or with non-operative treatment, including application of special medicated cream, use of stool softeners, avoidance of constipation. Some fissures, if they do not respond to these methods, may require an operation.
Commonly an ointment 0.2% GTN (glyceryl trinitrate) is used. This can result in long term healing of 40-50% and avoid the need for surgery. Botox injections may also selectively be used with healing rates of 50-60%.
What does surgery involve?
Sphincterotomy – The most common operation for this condition is a lateral anal sphincterotomy. This involves cutting a portion of one of the anal muscles which helps the fissure to heal by preventing pain and spasm and which improves the blood supply to the skin. Cutting this muscle rarely interferes with the ability to control bowel movements and can usually be performed without an overnight hospital stay.
Complete healing occurs in a few weeks, although pain often disappears after a few days.
Other operations less frequently performed include anal advancement flap.
Success from surgery is generally greater than 90-95%. If the problem returns without an obvious cause, the patient may need further assessment, including manometry testing or an examination under anaesthesia.
Can fissures lead to colon cancer?
No. Persistent symptoms need careful evaluation though, since conditions other than a fissure can cause similar symptoms.
What to expect after surgery
Usually the operation is performed as a “Day Case”. Some pain is expected at the site of the operation, with improvement over 3-5 days post-operatively. Pain killers will be given prior to discharge. Salt baths 3 times daily will keep the site of surgery clean and can also reduce pain. Usual work and home activities can be resumed within 3-5 day.