It may seem logical for healthcare providers to adopt incremental technology advances as they are introduced in order to deliver the best care to patients, but those increments need justification – especially in today's cost-conscious environment. Gastroenterologists at Mayo Clinic decided to see if high-definition (HD) colonoscopy detects more polyps than standard colonoscopes because no definitive studies have been performed. They now report that HD colonoscopy is much more sensitive than standard colonoscopy in finding polyps that could morph into cancer.
Details of the 2,430-patient study were presented this week at the American College of Gastroenterology (Bethesda, Maryland) meeting in San Diego.
"We don't know if it will translate into lower colon cancer risk and death rates," Michael Wallace, MD, the study's principal investigator, told Medical Device Daily. "But it should reduce the frequency of follow-up colonoscopies."
Wallace, who is a professor of medicine at the College of Medicine, Mayo Clinic (Jacksonville, Florida), said that all three Mayo Clinic sites in Florida, Rochester, Minnesota and Scottsdale, Arizona, now only use HD endoscopes to perform colonoscopies. A HD endoscope uses both a high-definition video chip and HD monitors to increase image resolution.
"In HD colonoscopes, there are 1,080 lines of resolution compared to 480 lines in standard," he said. "It's like upgrading your TV. HD picked up smaller polyps more than standard. If you just look at bigger polyps with high-grade dysplasia, both picked it up equally as well. We presume the polyps that are missed in standard colonoscopy will eventually grow bigger and be picked up later, but we didn't study that aspect specifically."
In general, all polyps are considered precancerous and the current standard of care is to remove them regardless of size.
This study was conducted between 2006 and 2007 when Mayo Clinic in Florida was in the midst of switching its six colonoscopy procedure rooms from standard colonoscopy endoscopes to HD endoscopes. Wallace said it was the perfect opportunity to study and compare.
In what Wallace calls a "natural randomization," patients were placed in whatever room was available and assigned a gastroenterologist who was on duty at the time. Physicians were not able to cherry-pick their patients or the procedure.
They found that the rate of detection of adenomas, precancerous polyps, was 29% among patients who were scanned with HD, vs. 24% for those in which standard endoscopes were used.
The 20% increase may seem small, but considering that 14 million colonoscopies are performed each year in the U.S., the small difference adds up.
"Our center has gone to all HD systems throughout the clinic," Wallace said. "Part of that is that the equipment is better and better. But this study provides justification that HD scopes detect more polyps."
He suggested that other facilities which have a mix of HD and standard colonoscopy systems might consider stratifying patients so that those with a high-risk profile for colon cancer are examined using the HD systems.
"If you are in a situation where you had to face a choice between HD and standard, it's likely the higher risk patients – those with a family history of colon cancer, history of previous polyps or cancer – should have colonoscopies with the best system available."
Wallace cautioned that as technology evolves, it's important to continue studying devices and "not to just accept that every technology advance necessarily leads to better care."
The study was funded by Mayo Clinic and compared the HD Olympus 180 series colonoscopy with standard definition Olympus 140-160 series colonoscopy, both made by Olympus (Center Valley, Pennsylvania).
Lynn Yoffee, 770-361-4789;