What Is Virtual Colonoscopy?
Computed Tomography scans (also known as CT or CAT scans), use special x-ray equipment to create cross-sectional images that appear as “slices” of the body and organs. When the colon is distended with gas, the resulting images can be viewed on a computer workstation, allowing the inner walls of the colon to be evaluated with 2-D and 3-D views. This gives a view of the colon similar to that seen during colonoscopy, which is a screening test for colon cancer performed by a gastroenterologist.
Virtual Colonoscopy can also be used as a screening test to evaluate individuals with a relatively low risk of colon cancer. You should consult with your personal physician as to which screening procedure is most appropriate for you.
What Should I Expect?
During the exam you will lie on a table that will move you into the doughnut-shaped scanner. Your technologist will watch you through an observation window and will be able to communicate with you at all times. At the beginning of the procedure, a tube will be placed in the rectum to allow the colon to be filled with air. This inflation is necessary to better evaluate the walls of the colon for possible polyps or masses. Once the colon is distended, you will be instructed on breath holding during the acquisition of images.
You may hear humming, buzzing, or clicking sounds as the CT machine moves to reposition you for the images. Two sets of images will be obtained, the first with you on your stomach and the second while on your back. Remaining still and following the breathing instructions are very important in order to obtain clear images. When scanning is complete, the technologist will return to help you from the table. You may eat normal meals unless other tests are scheduled. Your exam will take about 20 minutes, after which you will be able to return to your normal activities.
How Should I Prepare?
Before your exam, you will be given a special low fiber diet to follow. A diet kit, which includes laxatives and a mild barium preparation, will be given to you 48 hours prior to the procedure. The technologist will explain the kit and answer any questions you may have.
You should continue medications prescribed by your doctor unless informed otherwise. Diabetic patients may need to delay their medication on the morning of the exam until after they have eaten in order to avoid an insulin reaction. You may be asked to change into a hospital gown for the procedure. Women should always inform their technologist if there is any possibility of pregnancy.
How Do I Get the Results?
After your study is over, the images will be evaluated by one of our board-certified radiologists with expertise in Virtual Colonoscopy. A final report will be sent to your doctor, who can then discuss the results with you in detail. Should you have any questions regarding the Virtual Colonoscopy exam, we will be happy to discuss them with you.
Virtual Colonoscopy is available at Alamogordo Imaging Center and Northwest Imaging Center.