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Updated February 13, 2015.

What Are Anal Fissures?

When the lining of the anal canal develops a tear or a sore (also called an ulcer), it is called an anal fissure. The anal canal is the last part of the rectum before the anus. Fissures can occur in just about anyone, but are more common in middle aged or young adults. Risk factors for anal fissures include constipation, laxative abuse, multiple pregnancies, and Crohn's disease.

A fissure can be difficult to heal because it causes a spasm in the anal sphincter and aggravates itself, creating a vicious cycle of pain and irritation.

Symptoms

Symptoms of a fissure include:

• Bright red blood in the toilet bowel or on paper
• Painful bowel movements

Diagnosis

A fissure is typically diagnosed via either a visual or a digital rectal exam. A special tool called an anoscope or a sigmoidoscope may also be used. Either of these two tests can determine if any bleeding from the anus is truly from a fissure or caused by a different problem.

Causes

Fissures can be caused by constipation or by forcing a hard bowel movement through the anus, during childbirth, or ulceration of hemorrhoids.
There are several risk factors for fissures. These include:

• Anal sex
• Constipation
• Crohn's disease
• Chronic use of laxatives
• Immunodeficiency disorders
• Leukemia
• Multiple pregnancies

Treatment of Acute Fissures

Fissures are treated in a variety of ways. A physician will help you understand the treatments, their differences, and which one is most appropriate for you.

For acute fissures, treatment aims to lessen pressure on the anal canal by making sure stools are soft and to ease any discomfort or rectal bleeding. These methods include:

• Warm baths (or Sitz baths)
• Eating more fiber to create softer stools
• Stool softeners (as prescribed by a physician)
• Topical hydrocortisone (suppositories or foams)
• Zinc oxide
• Petroleum jelly
• Topical anesthetics for pain
• Topical nitroglycerin cream

Patients who have anal fissures may also be advised to try to avoid straining during a bowel movement, and to drink at least 8 glasses of water per day to prevent constipation. Cleaning the anal area with warm water after bowel movements may also be recommended. About 90% of fissures will heal without surgery.

Treatment of Chronic Fissures

If a fissure persists even after treatment, it may become a chronic problem. A chronic fissure may need to be treated with surgery. Two different types of surgery are done for fissures -- anal dilation and lateral internal sphincterotomy (LIS).

Anal dilatation may be a choice for some patients, but it is being used less often due to the potential of incontinence as a complication. During anal dilatation, the anal canal is stretched.

More often, the LIS surgery is used. LIS is usually done with a general anesthetic on an outpatient basis. In the procedure, a portion of the anal canal muscle is cut. The fissure itself is not removed, but any muscle spasms in the anus sphincter will be relieved. This will allow the fissure to heal at a cure rate of more than 90%.

After surgery, it is important to keep the anal area clean and dry. Moist wipes instead of toilet paper and a stool bulking agent may be recommended.

Newer Treatments

One new non-surgical method being researched for use in healing fissures is Botox (botulism toxin) injections. The injections work by weakening the anal muscles and thereby allow them to heal. This method is considered more invasive than other non-surgical options, but it has a higher success rate than treatment with nitroglycerin.

How Fissures Relate To Other Conditions

Fissures are more common in people with Crohn's disease than in those who have ulcerative colitis. Elderly people or those who have diabetes may have more difficulty in healing fissures. Fissures are not related to colon cancer.

Prognosis

The prognosis is good for acute fissures; they generally heal with non-invasive treatments. The cure rate using LIS surgery for chronic fissures is also encouraging. LIS can be repeated if the fissure does not heal with the first surgery. Fissures do not cause cancer and complications are uncommon.
<sub>Sources:

American Society of Colon and Rectal Surgeons. "Anal Fissure." American Society of Colon and Rectal Surgeons 2012. 1 Aug 2013.

Eisner T. "Anal fissure." ADAM July 9 2011. 1 Aug 2013.

Brisinda G, Cadeddu F, Brandara F, Marniga G, Maria G. "Randomized clinical trial comparing botulinum toxin injections with 0.2 per cent nitroglycerin ointment for chronic anal fissure." Br J Surg Feb 2007. 1 Aug 2013.</sub>