Figure 2b. CT scans in a 21-year-old man with nausea and abdominal pain, which were suggestive of acute appendicitis. (a) Nonenhanced transverse CT scan shows the inflamed appendix (arrow) in cross section. The appendix is easily identified because of the presence of abundant retroperitoneal fat and well-opacified adjacent small-bowel loops. Periappendiceal inflammation was absent. (b) Contrast-enhanced transverse CT scan shows abnormal mural thickening and enhancement of the slightly dilated, inflamed appendix (arrow).