Anal Stenosis

Anal stenosis, which is a narrowing of the anal canal that makes it difficult to pass stool, can lead to serious complications if left untreated. Also referred to as anal stricture, this condition occurs when the muscles in the anus—which expand and contract to regulate the passage of fecal material—narrow.

Anal Stenosis Causes

In the majority of cases, anal stenosis is linked to scar tissue formation, which can occur after trauma or hemorrhoid surgery. Other possible causes of anal stenosis include:

  • A congenital malformation
  • Venereal disease
  • Rectal infection

This condition most often affects the internal (involuntary) sphincter instead of the external sphincter, which a person can control.

Anal Stenosis Symptoms

The symptoms of anal stenosis might seem minor at first, but they can worsen with time. They include:

  • Constipation
  • Pain during bowel movements
  • Stools that are narrow and break apart like pellets
  • Bright red blood in the toilet after a bowel movement

Crohn’s disease, an inflammatory bowel disease, can also produce symptoms that mimic those of anal stenosis. When the symptoms of anal stenosis persist, they are usually a result of one or more of the following causes:

  • Constipation or straining during bowel movements
  • Anal or rectal tears
  • Complications from a surgical procedure, such as a hemorrhoidectomy
  • Irritation from constant diarrhea
  • Rectal infection

It’s important to understand that these factors themselves don’t result in anal stenosis, but the buildup of scar tissue they may produce in the anal canal can. Scar tissue is not as flexible as healthy muscle tissue, and it can restrict the anal canal if it accumulates.

Anal Stenosis Diagnosis

Diagnosing anal stenosis is relatively straightforward. In most cases, this condition is confirmed by reviewing symptoms and medical history, in addition to performing a brief physical or visual exam.

Anal Stenosis Treatments

The non-surgical treatment options for anal stenosis are limited, though fiber supplements, stool softeners, emollient laxatives and a high-fiber diet may help soften stools so they pass more easily. Common surgical options include an anoplasty, which is the surgical reconstruction of the anus, or a sphincterotomy, which involves the cutting of the internal sphincter muscle to reduce tension. These treatment approaches and many others are available from the experts at Tampa General Hospital’s Gastroenterology Institute.