Published results to date have indicated a high sensitivity of computed tomographic (CT) colonography for polyps measuring 6 mm or more [1-4]. These results, however, can be achieved only with meticulous attention to technique including full-bowel preparation, adequate colonic distention, and acquisition of supine and prone thin-section CT images. Further, there is a significant learning curve involved in the interpretation of CT colonographic studies, with performance statistics improving with operator experience [5]. Radiologists must be comfortable with "soft copy" reporting directly from workstation monitors and have access to and be familiar with software for multiplanar and endoluminal reconstructions. In addition, to maximize polyp detection and minimize false positive results, reporting radiologists must have a working knowledge of normal colorectal anatomy and pathology as shown on CT colonography and be familiar with potential pitfalls in interpretation. This review describes the normal colorectal anatomy as seen on CT colonography, highlights common pitfalls, and proposes tips for accurate CT colonographic interpretation.
