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A screening colonoscopy looks for polyps or cancer whether or not you have any specific risk factors—even if you have no symptoms. This test allows us to catch colon polyps and remove them to try to prevent cancer altogether, and to catch colorectal cancer in its earliest stages, when it is easiest to treat.
Preparing for Your Screening Colonoscopy (Colonoscopy Prep)
Before your colonoscopy, you need to clean out your colon (colon prep). Colon prep usually takes two days.
Colon prep can be time consuming and a little uncomfortable, but it is absolutely necessary for a quick and successful colonoscopy.
To make your prep successful, you should consume a liquid diet (such as clear broth, black coffee, tea, apple juice, clear soft drinks, and popsicles) the entire day before your colonoscopy.
Usually, we recommend a “split prep.” The evening before your colonoscopy and early in the morning on the day of your colonoscopy, you drink a liquid that triggers bowel-clearing diarrhea.
You should plan to stay home during this process since you will need to use the bathroom often.
Screening Colonoscopy Procedure
You lie on your side on the exam table with your knees drawn toward your chest.
We give you medication to help you relax and block any discomfort. Many people do not even remember the test after it is done.
We insert the colonoscope (a small flexible tube and tiny camera) into your rectum.
We use small amounts of water or carbon dioxide gas to inflate your colon, making it easier to pass the colonoscope, while also allowing better views of your colon.
The camera at the tip of the colonoscope sends images to a large video monitor, so we can examine the characteristics of your colon in great detail.
Once we reach the opening to your small intestine, we examine your large intestine very closely, as we slowly remove the colonoscope.
If we detect colon polyps, special tools allow us to completely remove polyps. If we detect other abnormalities, special tools allow us to take tissue samples.
After your procedure, you may feel a little bloated. Passing gas will help clear the carbon dioxide from your colon.
The Stanford Medicine Online Second Opinion program offers you easy access to our world-class doctors. It’s all done remotely and you don’t have to visit our hospital or one of our clinics for this service. You don’t even need to leave home!