New CAD System Detects Colon Polyps in Colons Previously Obscured by Contrast-Enhanced Fluid

A new computer-aided detection (CAD) system can help radiologists detect polyps in colons that contain contrast-enhanced fluid, says a new study that appears in the January 2005 issue of the American Journal of Roentgenology.

“As far as I know, we are the first to publish a CAD algorithm to find polyps submerged in contrast-enhanced colonic fluid; other CAD algorithms do not yet deal with this problem,” said Ronald M. Summers, MD, PhD, of the National Institutes of Health and lead author of the study. The benefits to the patient of having such a system as an option is that fewer polyps will be missed and the patient’s risk of developing colorectal cancer will be reduced, Dr. Summers said.

For the study, the researchers analyzed 17 patients who each had at least one proven colon polyp that was submerged in contrast-enhanced fluid, for a total of 22 polyps. The CAD system was able to find 19 of the polyps.

“The CAD algorithm can actually be used for the air-filled areas of the colon in addition to the fluid-filled portions, so that polyps surrounded by air, fluid or both can also be detected,” said Dr. Summers. The study authors describe the algorithm like a porpoise, that “jumps” from air present in the colon to fluid present in the colon and back again until all portions of the colon are identified.