Abdominal Imaging

, Volume 36, Issue 2, pp 153–164 | Cite as

Sources of false positives in computer-assisted CT colonography



The application of computer-aided detection (CAD) is expected to improve reader sensitivity and to reduce inter-observer variance in computed tomographic (CT) colonography. However, current CAD systems display a large number of false-positive (FP) detections. The reviewing of a large number of FP CAD detections increases interpretation time, and it may also reduce the specificity and/or sensitivity of a computer-assisted reader. Therefore, it is important to be aware of the patterns and pitfalls of FP CAD detections. This pictorial essay reviews common sources of FP CAD detections that have been observed in the literature and in our experiments in computer-assisted CT colonography. Also the recommended computer-assisted reading technique is described.


Computed tomographic colonography Computer-aided detection False-positives Image interpretation Colorectal neoplasms 



Computed tomographic






Computer-aided detection




Ileocecal valve


Electronic cleansing


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Massachusetts General Hospital and Harvard Medical SchoolBostonUSA

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