Virtual colonoscopy is a minimally invasive alternative to conventional colonoscopy (endoscopy) that screens the colon and rectum for polyps and early cancer before symptoms occur. Karen Horton, M.D., professor and Chair of Radiology, discusses what is involved in the procedure, how to prepare and the benefits of virtual colonoscopy over conventional colonoscopy. To learn more, please visit: http://www.hopkinsmedicine.org/radiology