What's virtual colonoscopy?
Virtual colonoscopy is the latest development in colon cancer detection. Virtual colonoscopy uses a Computer Tomography (CT) scanner and computer virtual reality software to look inside the body. The CT scan allows radiologists (special physicians with advanced training in x-ray imaging) to create pictures on the computer that look similar to those seen by a
colonoscopy.
There are some advantages and disadvantages of having a virtual colonoscopy instead of a colonoscopy. For example, it may reduce the number of colonoscopies performed for diagnostic purposes, and increase the number performed therapeutically for the specific purpose of removing polyps. Virtual colonoscopy is minimally invasive and is considered to be safer than colonoscopy, primarily because there is a very low risk of complications, including the tearing of the bowel.Unlike traditional colonoscopy, virtual colonoscopy is noninvasive and can be performed in a number of situations where traditional colonoscopy is contraindicated. It is also a good alternative for people who do not want to undergo traditional colonoscopy for a variety of reasons. The procedure makes use of sophisticated imaging techniques to generate a 3-D reconstruction of the inner surface of the colon, which can then be evaluated for abnormalities by specially trained radiologists.
Virtual colonoscopy is often well tolerated by patients and does not require sedation. When air is introduced in the colon some patients experience minimal temporary abdominal cramping or "gas pains.” An intravenous injection of a widely used medicine to relax the bowel can be given to help reduce gas pains, but this is usually not necessary.
However, at this point, virtual colonoscopy by CT does not provide the same information as colonoscopy. Therefore, virtual colonoscopy may be a useful complement to an incomplete colonoscopy. CT scans are known to miss flat polyps and polyps smaller than 5mm. As with any procedure, including colonoscopy, there are no guarantees that all clinically significant growths will be detected.
As the technology evolves, virtual colonoscopy is likely to emerge as a standard screening test, a task force of the American Gastroenterological Association (AGA) concluded in a report last week. But the panel's report in the journal Gastroenterology also cited a number of issues that need to be worked out before the test becomes widely accepted. |
