Figure 4d. Round polyp (6 mm) in 71-year-old man. (a) Transverse CT colonographic image shows a 6-mm mass (arrow) with smooth round borders on a haustral fold in the ascending colon. (b) Coronal CT colonographic image findings confirm that the mass (arrow) seen in a has a smooth round polypoid morphologic structure. (c) Three-dimensional volume-rendered endoluminal CT image shows the polyp (arrow) to have a round morphologic structure and smooth borders. (d) Corresponding colonoscopic image shows the same round polyp (arrow) with smooth borders.