Virtual colonoscopy is also known as CT colonoscopy, because it uses Computed Tomography (CT) scanning to render 2-D and 3-D images of a patient’s colon, which helps doctors look for polyps and other abnormalities and treat them quickly.
CT colonoscopy does not require sedation, and it is far less invasive than endoscopic colonoscopy. A small tube is inserted about two inches into the rectum, to deliver air into the colon; this takes any folds or wrinkles out of the colon tissue, to provide a better view. The patient is scanned twice, once face-up, and once facedown. The entire procedure usually takes about 15 minutes. Because CT colonoscopy eliminates the need to run an endoscope through the full length of the patient’s colon, there is far less discomfort, and significantly less risk of perforating the colon while imaging its interior.
In addition to routine screenings for low-risk patients, CT colonoscopy may be a better alternative to endoscopic colonoscopy for patients who are elderly or frail, people who take certain medications like blood thinners, or patients who have a blockage or narrowing of the bowel. CT colonoscopy is less expensive than conventional endoscopy, and private insurance companies who participate in the Affordable Care Act insurance exchange program are required to cover the procedure.