Anorectal function testing including evaluation of constipation and fecal incontinence

These tests diagnose constipation caused by an abnormal functioning of the anus or rectum

Anorectal function testing includes a number of specific tests that are helpful in the diagnostic assessment of patients with fecal incontinence and constipation; their purpose is to delineate the pathophysiological mechanism for these symptoms.

Some of these tests may also provide helpful information in the assessment of patients with rectal pain or diarrhea, but their sensitivity and specificity are less well established for these symptoms. Tests for which there is consensus regarding the clinical utility include:

• resting anal canal pressure,
• anal canal squeeze pressure (peak pressure and duration),
• the rectoanal inhibitory reflex elicited by balloon distension of the rectum,
• anal canal pressure in response to a cough,
• anal canal pressure in response to defecatory maneuvers,
• simulated defecation by means of balloon or radiopaque contrast,
• compliance of the rectum in response to balloon distension,
• sensory thresholds in response to balloon distension.

Chronic constipation is infrequent bowel movements or difficult passage of stools that persists for several weeks or longer.

Constipation is generally described as having fewer than three bowel movements a week.

Though occasional constipation is very common, some people experience chronic constipation that can interfere with their ability to go about their daily tasks. Chronic constipation may also cause excessive straining to have a bowel movement and other signs and symptoms.

Treatment for chronic constipation depends in part on the underlying cause. However, in some cases, a cause is never found.

Fecal incontinence is the inability to control bowel movements, causing stool (feces) to leak unexpectedly from the rectum. Also called bowel incontinence, fecal incontinence ranges from an occasional leakage of stool while passing gas to a complete loss of bowel control.

Common causes of fecal incontinence include diarrhea, constipation, and muscle or nerve damage. The muscle or nerve damage may be associated with aging or with giving birth.

Whatever the cause, fecal incontinence can be embarrassing. But don't shy away from talking to your doctor. Treatments are available that can improve fecal incontinence and your quality of life.