New Techniques, Cameras Improve Colonoscopy
Technology Making Colonoscopy More Accurate
Oct. 27, 2009 (San Diego) -- The screening test no one likes to talk about,
colonoscopy, is getting more accurate, thanks to better techniques and
equipment, such as a camera that helps detect polyps and other lesions lurking
behind the folds of the intestines.
That was the message at a news briefing at the annual meeting of the
American College of Gastroenterology in San Diego.
A routine colonoscopy, a visual inspection of the colon using a special flexible scope, is generally
recommended at age 50 to detect cancer and precancerous
growths, and earlier if there is a family history or for certain ethnic
But the test isn't foolproof, and researchers have been trying to improve
A 'Third Eye' for the Colon
One improvement in colonoscopy is a disposable device that is passed through
the instrument channel of a standard colonoscope, called the Third Eye
Retroscope (TER), which gives physicians a better look at the lesions they
may miss with standard screening equipment.
''The third eye is a camera on the end of a probe,'' says researcher Daniel
C. DeMarco, MD, medical director of endoscopy at the Baylor University Medical Center, Dallas.
It allows physicians to inspect the colon backward as they withdraw the
''The image is not quite as clear [as the forward image],'' he says. Still,
the idea is to help physicians detect the lesions -- polyps and adenomas --
behind the many folds and turns in an intestine, which has remained difficult
despite other advances in equipment.
At the meeting, DeMarco presented
the results of his study, in which nearly 300 patients underwent colonoscopies
using the third eye camera. By using a split screen monitor, DeMarco's team was
able to detect which growths were observed due to the camera that wouldn't have
been detected with traditional colonoscopy alone. The overall increased
detection rate for all adenomas using the third eye device was 16%, with an
even greater detection rate for larger growths than smaller ones.
Is High-Definition Better?
High-definition colonoscopy may detect more lesions than standard ''white
light'' colonoscopy, according to researcher Kenneth R. DeVault, MD, a
gastroenterologist at the Mayo Clinic in Jacksonville, Fla.
As the high-definition equipment was being phased in, DeVault's team
assigned 1,200 patients to standard exams and another 1,200 to high-definition
exams, then compared the detection rate of adenomas.
''Overall we found adenomas in about 30% who had high-definition and in 24%
of those who had standard-definition colonoscopy," he says.
But most were small, he says. High-definition is not available everywhere,
he says, although the newer machines are now high-definition. So in time, the
technology will be widespread.