What is a Colonoscopy?


A colonoscopy is a procedure that allows a gastroenterologist to examine the entire length of the colon for polyps, lesions or abnormalities. The patient is under sedation during the entire procedure. Using a colonoscope (a flexible tube with a small camera), the doctor can look for abnormalities and remove them for biopsy and diagnosis.


Colonoscopy is the preferred method for colon cancer screening because colon cancer can be both detected and removed during the same procedure. Other types of screening can detect the presence of cancer cells, but a positive test result means a follow-up colonoscopy will be needed.

A quality colonoscopy is the only screening that can both detect and prevent colon cancer. During a colonoscopy, your doctor can find and remove polyps (adenomas) before they have a chance to turn into cancer.

Those at average risk for colon cancer will likely only need a colonoscopy once every 10 years. Therefore, it is important to research the skill of the gastroenterologist. Consider these three factors when looking for a specialist to perform your colonoscopy, and don’t hesitate to ask them for this information:

Adenoma Detection Rate (ADR)

According to gastroenterologist Paul Brown, MD, of Louisville Endoscopy Center, “Adenoma Detection Rate is the percentage of time that at least one adenomatous polyp is detected during a physician’s screening colonoscopies. Therefore, knowing a physician’s ADR is an important factor in selecting the specialist with whom you feel most confident performing your colonoscopy.”

Cecal Intubation Rate

During a colonoscopy, the colonoscope should reach the start of the colon (the cecum) to ensure the entire colon has been examined. The cecal intubation rate is a measure of how often a physician is able to view the entire length of the colon during colonoscopies. A physician’s cecal intubation rate should be greater than 95 percent for screening colonoscopies.

Withdrawal Time

Another colonoscopy measure to consider is withdrawal time. Colonoscopies require time for the gastroenterologist to scope the entire colon from cecum to rectum for adenomas or polyps. Withdrawal time refers to how quickly the colonoscope is removed from the colon once the scope reaches the cecum.

Schedule a Colonoscopy Today

It is estimated that between 60 and 90 percent of colon cancer deaths could be prevented if everyone age 45 and older had colonoscopy screenings. If you are currently scheduled for a colonoscopy, be sure to read and follow your colonoscopy prep instructions. If you have not yet scheduled a colonoscopy, take a few moments to view some FAQs and find a center near you.

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