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(tinyurl.com/n8qzw4l) was the first to definitively show that high-definition scopes increase adenoma detection rates. Other groups have
backed the findings.
But HD results in a relatively small increase, says Michael B.
Wallace, MD, gastroenterologist and professor of medicine at the
Mayo Clinic in Jacksonville, Fla. He points to a large meta-analysis of
HD studies that showed the absolute increase in detection rate was
about 3%.
Studies show that adding narrow band imaging (NBI) to HD also
fails to increase detection rates, according to Dr. Wallace. "There's no
statistical difference between HD and HD plus NBI," he says.
However, other studies that have compared the combination of HD
and NBI to older-generation scopes — standard definition models
without NBI — have shown a significant reduction in adenoma miss
rates when the newer technology is used.
Dr. Wallace conducted a randomized controlled trial of colonoscopies performed consecutively on the same patients with both HDNBI scopes and standard definition scopes without NBI. He found
that colonoscopies performed with HD-NBI scopes resulted in fewer
missed polyps.
"All of the missed polyps were quite small and probably not of great
clinical significance, but they were missed nonetheless," says Dr.
Wallace.
He says a study conducted by German researchers that compared
adenoma detection rates between standard definition scopes and HDNBI scopes showed the combination resulted in much higher adenoma detection rates.
"Each incremental technology change — from HD to NBI, for
example — makes a relatively small difference in polyp detection
rates," says Dr. Wallace. "But combining all of the technologies,
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O U T PAT I E N T S U R G E R Y M A G A Z I N E O N L I N E | N O V E M B E R 2013
