Diagnosis of Fecal Incontinence

The doctor will ask health-related questions and do a physical exam and possibly other medical tests.

• Anal manometry checks the tightness of the anal sphincter and its ability to respond to signals, as well as the sensitivity and function of the rectum.
  
  
• Anorectal ultrasonography evaluates the structure of the anal sphincters.
  
  
• Proctography, also known as defecography, shows how much stool the rectum can hold, how well the rectum holds it, and how well the rectum can evacuate the stool.
  
  
• Proctosigmoidoscopy allows doctors to look inside the rectum for signs of disease or other problems that could cause fecal incontinence, such as inflammation, tumors, or scar tissue.
  
  
• Anal electromyography tests for nerve damage, which is often associated with obstetric injury.

source: http://digestive.niddk.nih.gov/ddiseases/pubs/fecalincontinence/index.htm