Colonoscopy
Learn more about what you can expect during your colonoscopy from The American Society of Gastrointestinal Endoscopy.
What is colonoscopy?
Colonoscopy is a procedure that uses a long, flexible, narrow tube with a light and tiny camera on one end, called a colonoscope or scope, to look inside the rectum and entire colon.
Colonoscopy can show irritated and swollen tissue, ulcers, and polypsâ€â€extra pieces of tissue that grow on the lining of the intestine.
Why is a colonoscopy performed?
A colonoscopy is performed to help diagnose
- changes in bowel habits
- abdominal pain
- bleeding from the anus
- weight loss
A gastroenterologist also performs a colonoscopy as a screening test for colon cancer.
How does a person prepare for a colonoscopy?
Preparation for a colonoscopy includes talking with a gastroenterologist about medical conditions the person has and medications the person is taking, arranging for a ride home after the procedure, and cleansing the bowel.
The gastroenterologist will give written bowel prep instructions to follow at home. A gastroenterologist orders a bowel prep so that little to no stool is present inside the person’s intestine.
The gastroenterologist will not be able to see the colon clearly if the prep is incomplete.
How is a colonoscopy performed?
A gastroenterologist performs a colonoscopy at a hospital or an outpatient center. For the test, the person will lie on a table while the gastroenterologist inserts a colonoscope into the anus and slowly guides it through the rectum and into the colon.
The gastroenterologist can remove polyps during colonoscopy and send them to a lab for testing. The gastroenterologist may also perform a biopsy, a procedure that involves taking a small piece of intestinal lining for examination with a microscope.
What are the risks of colonoscopy?
Bleeding and perforation are the most common complications from colonoscopy.
Source: National Digestive Diseases, Information Clearinghouse (NDDIC), Colonoscopy.