Virtual colonoscopy (VC, also called CT Colonography) is a medical imaging procedure which uses x-rays and computers to produce two- and three-dimensional images of the colon (large intestine) from the lowest part, the rectum, all the way to the lower end of the small intestine and display them on a screen. The procedure is used to diagnose colon and bowel disease, including polyps, diverticulosis and cancer. VC is performed via computed tomography (CT), sometimes called a CAT scan, or with magnetic resonance imaging. Not to be confused with a similar procedure called a CT Pneumocolon, a virtual colonoscopy can provide 3D reconstructed endoluminal views of the bowel.