AJR:193, November 2009
^^^_ wo imaging techniques, optical 1 colonoscopy (OC) and CT colonography (CTC), are used to I detect polyps. Some patients undergo both examinations, so comparison of polyp loci is important. Correlation of polyp location relative to the anus in OC and CTC is reported independently in this issue of AJR by Summers et al. [1] and by Duncan et al. [2]. Their results indicate that CTC to OC correspondence based on centerline distances measurements is robust.