CHICAGO — Virtual colonoscopy, a cancer-detecting procedure that gives doctors a computer-generated 3-D view of the colon, is less reliable than previously thought and not ready for widespread use, researchers said in a study in today's Journal of the American Medical Assn.
Its accuracy varies considerably depending on the training and methods of the doctors performing it, according to a study of 600 patients at nine major clinics.
For The Record
Los Angeles Times Saturday May 15, 2004 Home Edition Main News Part A Page 2 National Desk 1 inches; 49 words Type of Material: Correction
Colonoscopy -- An article in Section A on April 14 about virtual colonoscopy said that conventional colonoscopy used a flexible tube about the thickness of a garden hose to probe the colon. The tube is about the thickness of a finger, according to the American Society for Gastrointestinal Endoscopy.
In conventional colonoscopy, a long, flexible viewing tube about the thickness of a garden hose is inserted in the rectum and threaded several feet into the colon.
A device on the end of the tube is used to remove suspicious growths, which are later tested for cancer.
In virtual colonoscopy, a narrower rectal catheter is inserted and a CT scanner produces images of the colon.
In the study, the virtual method had a 55% success rate in detecting when patients had at least one suspicious polyp at least 10 millimeters in diameter, compared with a 100% success rate for traditional colonoscopy.