2016-06-16 15:19:06 UTC

Colonoscopy 102: What is the Purpose of a Colonoscopy?

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A colonoscopy is the main way to check for diseases of the colon, such as colitis or cancer, and to remove colon polyps. 

  • A polyp is a mushroom-like growth on the inside wall of the colon or rectum. 
  • Polyps grow slowly over many years. 
  • Some polyps become cancerous, others do not. 

A colonoscopy is also a safe and helpful way to look at health issues in the gastrointestinal (GI) tract, such as:

  • Belly pain that won’t go away.
  • Rectal pain that won’t go away.
  • Blood in your stool.
  • Change in bowel habits, such as diarrhea (loose stool), that won’t go away.
  • Inflamed (swollen) colon that is seen on a computerized tomography (CT) scan.

During a colonoscopy, tools can be passed through the colonoscope, which is a long, thin (about the width of your little finger), flexible tube with a tiny camera and a light on the end, to painlessly remove a suspicious-looking growth or to biopsy (take a small tissue sample). 


© AGA, September 2017

©AGA, July 2016

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