Virtual Colonoscopy produces images comparable to traditional colonoscopy without the use of sedation or an endoscope. Air is pumped into the colon and images are then taken on a CT scanner. You may be asked to lie in different positions while a series of images are taken. This movement allows the radiologist to differentiate between fecal matter and potentially cancerous polyps.
You may feel some discomfort during the exam as a result of the air in your colon. The air is necessary to inflate your large intestines and produce 3D images that mimic what would be seen during traditional colonoscopy. Also like traditional colonoscopy, a cleansed bowel is necessary to produce diagnostic images. You will be required to undergo the same preparation as traditional colonoscopy.
Studies have shown virtual colonoscopy to be effective as traditional colonoscopy in diagnosing polyps 6mm and greater. Despite this fact most insurance companies do not cover this exam as a first means of diagnosis. Should you have a failed colonoscopy, are unable to undergo sedation protocols, or have been diagnosed with sever coagulopathy, your insurance company may then extended coverage for a virtual colonoscopy. Inability to tolerate exam preparation will not make you a candidate for virtual colonoscopy as the preparation requirements are the same.
Unlike traditional colonoscopy, any polyps found from your exam will not be removed at the time of your CT scan. If polyps are found after a virtual colonoscopy, you may have to have an endoscopic colonoscopy to remove the polyps or be scheduled for surgical removal if the polyps are believed to be cancerous.
Patient Preparation for Virtual Colonoscopy
Your referring physician will provide you with a prescription for medications that will cleanse your bowels. You must complete your preparations as prescribed or we will not be able to perform your exam.
On the day of your exam you should wear comfortable, loose-fitting clothing for your CT exam. Metal objects can affect the image, so avoid clothing with zippers and snaps. You may be asked to remove hairpins, jewelry, eyeglasses, hearing aids and any removable dental work that could obscure the images. You also may be asked to refrain from eating or drinking anything for an hour or longer before the exam. Women should always inform their doctor or technologist if there is any possibility that they are pregnant.
For the most up to date information, visit www.radiologyinfo.org, a website dedicated to radiology information from the patient perspective.