Diagnosis of fecal incontinence is made tentatively with a thorough medical history from the patient and physical examination. Then, the following tests are used to either confirm the diagnosis or rule out other conditions that can cause similar symptoms.

Anorectal ultra-sonography

  • Assesses the anal sphincter muscle structure and tone
  • How it’s done: A probe is then inserted into the rectum. High frequency sound waves are emitted. The echo pattern is then converted into an image.

Anal manometry

  • Evaluates rectal contractions and sensitivity
  • How it’s done: A small, flexible tube with a balloon at one end is inserted into the rectum. The tube is connected to a machine where pressure is measured. The small balloon is inflated in the rectum to evaluate the normal reflex pattern. During the test, you may also be asked to squeeze or tighten the sphincter for further measurement.

MRI (magnetic resonance imaging)

  • Looks for abnormalities throughout the digestive system; can provide images of the anal sphincter muscles
  • How it’s done: You are asked to lie on your back on a table with head, torso and arms strapped down to prevent movement. The table then slides into the tunnel-like space that contains a magnet. You may hear banging or tapping noises from the magnet movement but are often offered piped in music to soothe you and mask the noise. Images are taken in body cross sections. The test usually takes 30-60 minutes and is painless.

Proctography (also known as defecography)

  • Demonstrates the amount of stool the rectum holds and rectal capacity. Also shows the efficiency of stool elimination by the rectum.
  • How it’s done: A caulk gun device is inserted rectally with infusion of barium paste. You are then transferred to a portable commode adjacent to a fluoroscope that records defecation. An x-ray camera visualizes the buttocks, lower pelvis and rectum.

Proctosigmoidoscopy

  • Searches for tumors, inflammation, or scar tissue in the rectum and lower section of the large intestine
  • How it’s done: First, the doctor slowly inserts a gloved finger into the anus to assess any inflammation or blockage. A lubricated tube with a lens and light is then inserted into the anus and upward into the rectum and lower colon. Air is blown through the scope to dilate the colon and improve visualization. Any watery stool, liquid, blood or mucus is aspirated through the scope.

Anal electro-myography

  • Measures the integrity of nerve impulses to rectal muscles and the pelvic floor
  • How it’s done: A small plug electrode is inserted into the anal canal. You’re then asked to relax, squeeze, and push while the anal sphincter muscle electrical activity is recorded and displayed on a computer screen.

CT Scan (computed tomography)

  • Used to detect enlargement or abnormalities of organs, blood vessels, lymph nodes, and soft tissue of the body; used to guide biopsies to affected areas and to guide needles for minimally invasive tumor treatments; helps in radiation treatment administration; helps to stage cancers and determine success of chemotherapeutic treatments
  • How it’s done: You will be asked to lie on a narrow examination table. An intravenous needle and line may be inserted. You may be asked to swallow contrast material, which may be slightly unpleasant. Restraints may or may not be used to maintain a still position. The table then slides into the center of a tunnel-like machine. The X-ray tube rotates around you and you may hear banging as imaging takes place. A speaker and microphone may be fixed into the chamber allowing you to talk to and hear the technician as well as hearing piped-in music.