Virtual Colonoscopy : How & Why?

Usually, the first symptoms of colon cancer appear once it's too late and colon cancer patients are already into Stage III, where the survival rate is down to about 40%. Yet, if caught early, this deadly disease is 93 to 100% curable. Each year, 49,920 Americans die of metastatic colon cancer that has migrated throughout their bodies into other organs. In the beginning, a virtual colonoscopy can find the tiniest abnormalities, like non-cancerous colon polyps, that can be easily removed with a colonoscope or minimally invasive laparoscopic surgery.

To prepare for a virtual colonoscopy, you will need to complete a bowel prep, just like with a normal colonoscopy prep. You will need to empty all solid waste materials from your gastrointestinal tract by sticking to a clear liquid diet for 1 to 3 days before the procedure. This means you may only consume fat-free broth, strained fruit juice, water, coffee, tea, Gatorade and Jell-O. The night before your colonoscopy screening, you will take a laxative (in pill or powder format) to loosen your stools and increase the frequency of your bowel movement until everything has been cleared from your system. Just before the exam, you'll drink a contrast liquid, which will make your large intestine appear very bright during the scan so abnormal cells will stand out better.

During the virtual colonoscopy, you'll be positioned on the CT examination table, usually lying flat on your back. During a CT scan, a thin tube is then placed into the anus and rectum. Gas will be pumped through the tube to expand the large intestine for a clearer picture. For an MRI scan, contrast media will be administered rectally to expand the large intestine. The computer will then take images of the large intestine/colon, as patients are asked to hold their breath for about fifteen seconds to steady the images. A second pass is done after patients roll over onto their stomachs. Once the scan is done, the tube is removed and the patient is free to leave. The whole procedure only takes 15 minutes and doctors can read the results within 30 minutes.

There are several cons to getting a virtual colonoscopy. For one, you will still need to go through the same bowel prep and liquid dieting. Secondly, you will still need something inserted into you (albeit, not as deep) to complete the test. Thirdly, it may be difficult to find a place to have this test done in your area. Additionally, not every insurance company (for instance, Medicare) will cover it. There are small risks involved too. Inflating the colon with air could possibly perforate the bowel (which has happened in less than 1/2,000 cases). There is also a small cancer risk from radiation exposure, although the dose is just 5 mSv, which is about 20 months' worth of what a person normally receives in radiation from everyday life. Also, these scans are unsafe for pregnant women and may not be advised for obese individuals. If colon polyps need to be removed, a traditional colonoscopy will need to be performed after all.