If something is found in your stool test, your doctor will likely call for a colonoscopy. You might have the choice of doing either a virtual or a traditional colonoscopy. Many patients prefer a virtual colonoscopy, as it is less invasive than the traditional. A virtual colonoscopy uses a CT scan – a medical imaging technique that collects in-depth images of your colon. During this procedure, a small tube is put in the rectum to create air in the colon that makes it easy for your doctor to view images of the abdominal organs. The procedure takes about 10 minutes and does not require sedation – a fact that makes many patients prefer this method.