August 1, 2006 Gastroenterologists Use Hi-Res Narrow-Band Imaging To Find Cancer New optical technologies are helping gastroenterologists improve cancer detection using colonoscopy. A new endoscope uses HDTV technology for better resolution, and can switch from white light imaging to narrow-band blue light, which provides better detail of the intestine's linings, especially of blood vessels.
CHARLOTTESVILLE, Va. -- A colonoscopy is the gold standard for detecting colon cancer. Now, adding an HDTV signal and color change to the procedure could make the screening process more accurate in detecting the disease.
Like 70 million Americans, Kathy Chrisman suffers with digestive tract diseases. But she's learned to cope. "I do fairly well even with the 20-year history of medical problems," she says.
Chrisman's endured many colonoscopies to try and diagnose her illnesses, but hopefully today's will be her last. Her gastroenterologist is using a new endoscope combining HDTV technology and narrow-band imaging that uses blue light to see inside the colon in a whole new way.
"The blue light is an enhancement of the white light, because it provides greater detail of the lining of the intestine," Paul Yeaton, of the University of Virginia in Charlottesville, tells DBIS.
Traditional colonoscopies use white light to view the colon, but using blue light emphasizes features of the colon that are usually hard to see.
Dr. Yeaton says, "When we turn on the blue light, the blood vessels become much more prominent in their appearance, and the surface of the intestine -- the detail of that is also increased."
HDTV technology improves the view of the procedure.
"The benefit is to have a better diagnosis or the possibility of detecting some abnormal growth earlier," Dr. Yeaton says.
The new imaging technique helped Chrisman's doctor determine she has inflammation of the colon, a treatable problem caught just in time.
Narrow-band imaging with the blue is used in conjunction with traditional white light colonoscopies. Doctors have the ability to switch from white light to blue light when better-enhanced images are needed.
BACKGROUND: Scientists have developed the world's first system capable of delivering both high definition and narrow-band imaging technology to gastrointestinal examinations. The ability to get a picture of the digestive tract in greater detail helps doctors to better detect worrisome growths inside the colon, like polyps and precancerous lesions. UVA doctors are receiving a half-million-dollar upgrade in endoscopes as part of ongoing efforts to make the most advanced technology available to patients.
HOW IT WORKS: Narrow band imaging works by changing the white light emitted by the endoscope to a bluish light, which has a narrower wavelength. The blue light gives a greater visual contrast of the surface structure of the body parts being examined. Combining this with the HDTV signal from a video processor offers very clear views of anatomical structures and fine capillaries, and most notably changes that are characteristic of lesions, such as a slight thickening of the mucosa.
WHAT ARE COLONOSCOPIES? Colonoscopies are viewed as the "gold standard" for catching colorectal cancer before it has a chance to take root and spread. Gastroenterologists recommend that men and women over the age of 50, without a risk of colon cancer, get a colonoscopy every ten years, while those at high risk should receive one earlier and more frequently. In colonoscopies, physicians visually examine the lining of the colon and rectum. Upper endoscopies are used to examine the esophagus, stomach and the upper part of the small intestine (the duodenum). The colonoscope is a thin flexible instrument measuring between 48 inches to 72 inches long. It has a small video camera attached to the end so it can record images of the large intestine. The "scope" is passed through the rectum and into the colon to directly examine the lining of the lower digestive tract -- a full five feet of twists and turns.
Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.