Computerized Tomography Colonography: A Primer for Gastroenterologists Perry J. Pickhardt, David H. Kim  Clinical Gastroenterology and Hepatology  Volume 6, Issue 5, Pages 497-502 (May 2008) DOI: 10.1016/j.cgh.2008.02.048 Copyright © 2008 AGA Institute Terms and Conditions

Figure 1 Low-dose screening CTC examination in an asymptomatic average-risk 50-year-old woman. (A) The 3D colonic map marks the location of 2 colonic abnormalities identified at CTC, one in the ascending colon near the hepatic flexure (arrows) and the other in the midsigmoid colon (arrowhead). (B) 3D endoluminal CTC image shows a large, lobulated mass in the distal ascending colon that measured 5 cm and was highly concerning for invasive cancer. (C) 2D transverse prone CTC image confirms the large, nonobstructive, soft-tissue mass (arrow) near the hepatic flexure. No definite metastatic disease was identified on this noncontrast examination or at subsequent intravenous contrast-enhanced CT (not shown). (D) 2D transverse prone CTC caudal to C shows an area of annular soft-tissue thickening and luminal narrowing involving the sigmoid colon (arrowheads), which had a similar appearance on the supine view (not shown). This strictured segment was less bulky than the mass in the ascending colon. (E) Curved reformatted 2D coronal CTC image simultaneously shows the distal ascending colon mass (arrow), which proved to be stage I adenocarcinoma, and the midsigmoid lesion (arrowheads), which proved to be endometriosis. Clinical Gastroenterology and Hepatology 2008 6, 497-502DOI: (10.1016/j.cgh.2008.02.048) Copyright © 2008 AGA Institute Terms and Conditions

Figure 2 Screen capture of the CTC software system used for interpretation at the University of Wisconsin. This system allows for automated 3D endoluminal fly-through along a predetermined centerline, with immediate 2D correlation for suspicious findings. Secondary 2D evaluation for polyps can supplement 3D evaluation. In addition, there are a number of useful diagnostic tools that increase both the accuracy and diagnostic confidence for interpretation. Clinical Gastroenterology and Hepatology 2008 6, 497-502DOI: (10.1016/j.cgh.2008.02.048) Copyright © 2008 AGA Institute Terms and Conditions