An anal fissure is a small tear in the lining of the anus that can cause severe pain and minor bright red bleeding during and immediately following a bowel movement. They are quite common in the general population and are often confused with another cause of bleeding, hemorrhoids. A chronic fissure is defined as a tear that has not healed after 6 weeks or more. Fissures can occur at any age and occur equally between men and women. About 85% of fissures are at the posterior midline. An additional 10% occur anteriorly. Location of a chronic fissure away from the midline should raise a suspicion for other disease processes such as Crohn’s disease or a sexually transmitted disease (STD).
What causes an anal fissure?
The primary cause of an anal fissure is a hard, dry bowel movement. Other causes of a fissure include diarrhea and inflammation of the ano-rectal area. Patients will note severe pain during and following a bowel movement that can last for a few minutes or as long as several hours. It is not uncommon for patients to become fearful of having a bowel movement.
How is anal fissure treated?
The majority of anal fissures heal either by themselves or with non-operative treatment.
Non-operative treatment includes:
– High-fiber diet with lots of fruits, vegetables and grains.
– Daily fiber supplement such as Metamucil, Citrucel or Konsyl (total daily fiber intake goal is between 25 and 30 grams).
– 6 to 8 glasses of water daily.
– Soaking in warm water for about 10 minutes 2 to 3 times per day.
– A daily stool softener such as Colace or Surfak.
– Avoid foods that can cause constipation such as cheese, pasta, white rice, white bread.
– Narcotic pain medications are not recommended for the treatment of anal fissures, as they promote constipation.
For chronic fissures, other topical medications such as a specialized formulation of nitroglycerin or calcium-channel blockers may be prescribed when a patient has a more chronic-type fissure that promotes relaxation of the anal sphincter muscles. A surgeon will go over benefits and side-effects of each of these. Chronic fissures are generally more difficult to treat, and the surgeon may advise surgical treatment following attempts at medical management. In rare circumstances, Botox may be an appropriate intervention prior to an operation.
Surgery consists of precise and controlled cutting of a portion of the internal anal sphincter muscle to break the spasm and allow the fissure to heal, as well as removing any scar tissue around the fissure. The surgery is performed as an outpatient, same-day operation. Cutting this muscle rarely interferes with the ability of control bowel movements, although 5 to 10% of people can have occasional incontinence to gas and minor seepage of mucous at night. Complete healing occurs in a few weeks, although pain often disappears after a few days. Surgery is 95% successful.