Review of CT colonography: Current and future techniques

CT colonography combines spiral CT technology and advanced three- dimensional graphics software to generate endoluminal images of the colon. The combination of three-dimensional endoluminal, axial, and two-dimensional reformatted CT images has the potential to be a sensitive imaging modality for the detection of colorectal lesions. The early reported sensitivities and specificities using CT colonography for the detection of colorectal polyps are encouraging. This article reviews the screening methods currently used to detect colorectal carcinoma and the significance of early detection. The discussion then focuses on patient preparation, colonic insufflation, imaging protocols, CT parameters, postprocessing methods (surface and volume- rendering), and image interpretation during CT colonography.