ZocdocAnswersWhat is the difference between a colonoscopy and a CT scan virtual colonoscopy?

Question

What is the difference between a colonoscopy and a CT scan virtual colonoscopy?

I thought I was going to have a colonoscopy but my doctor says it is only a virtual colonoscopy. How are these different. I'm 57 and the virtual colonoscopy sounds nicer.

Answer

Virtual CT colonoscopy is a relatively new technology that some doctors suggest as an alternative for colon cancer screening in those patients who wish to avoid traditional colonoscopy. Both procedures require the same type of preparation, which may include a combination of tablet stool softeners and a large-volume liquid laxative, such as GoLytely. Patients undergoing the CT colonoscopy will have a small tube inserted in the rectum which will insufflate the colon with air. A CT scan will then be performed, in which x-ray radiation is used to generate detailed images of the inside of the colon. No sedation is required for the procedure. In a traditional colonoscopy, the exam involves the insertion of a scope with a camera into the rectum and this is advanced throughout the colon. The exam is done under sedation. If an abnormality is found, then the doctor can take a sample (or remove a polyp) during the same procedure. The exam also allows for actual visualization of the inside of the colon, with the ability to detect smaller polyps and abnormal flat lesions that may not be seen on CT. With a CT colonoscopy, any abnormality that is seen cannot be acted upon, and will require a traditional colonoscopy for further work-up and treatment.

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