Balloon-Enhanced Colonoscopy Finds More Adenomas

Laird Harrison

October 26, 2021

LAS VEGAS — The G-EYE colonoscope facilitates detection of adenomas more so than does the Endocuff Vision, researchers say.

In the first head-to-head comparison of two mechanical enhancement colonoscopy devices, "the G-EYE demonstrated a meaningful increase in adenoma detection rate [ADR] over Endocuff, particularly for advanced adenomas," said Seth Gross, MD, a professor of medicine at New York University Grossman School of Medicine, New York City.

Previous studies have shown that mechanical enhancements are more effective than optical enhancements, Gross said. "To take it a step further, when you look at mechanical devices, especially these two, in past studies, the G-EYE has been sort of the leader in adenoma detection," he told Medscape Medical News.

But until now, no studies had compared them head to head, said Gross, who presented the finding here at the American College of Gastroenterology (ACG) 2021 Annual Scientific Meeting.

The two devices work differently. The Endocuff Vision fits onto the colonoscope tip. During withdrawal, it expands radially, and its arms flatten the folds within the colon. The G-EYE balloon is deflated at insertion, then is inflated at the cecum, smoothing the colon wall while centering the colonoscopic view.

To compare the two, Gross and colleagues randomly assigned 363 patients to undergo colonoscopy with G-EYE and 364 patients to undergo colonoscopy with Endocuff Vision. The two groups were similar in demographics.

Withdrawal times were >6 minutes in both groups. The researchers detected adenomas in a higher percentage of patients with the G-EYE than with the Endocuff Vision. The same was true for advanced adenomas.

When using the G-EYE, the researchers also found more adenomas per patient, more sessile serrated adenomas per patient, more large adenomas per patient, and more right colon adenomas per patient.

Table. Detection Rates Compared

Device Adenoma detection rate, % Advanced adenoma detection rate, % Adenomas per patient
G-EYE 60.88 23.97 1.21
Endocuff Vision 51.10 11.81 1.04
P value < 0.05 < 0.05 < 0.05


The benchmark for ADR is only 25%, Gross said, suggesting that both devices are a worthwhile improvement over standard colonoscopes. "It supports the past literature that a mechanical enhancement is something that should be considered during colonoscopy," he said.

Costs differ as well. The G-EYE requires a permanent modification to the bending rubber of the colonoscope, so the cost is up front. The Endocuff Vision utilizes a single-use cap that is placed on the tip, so costs are spread over time.

The G-EYE gained US Food and Drug Administration (FDA) clearance in May 2020. In 2016, the Endocuff (an earlier version of the Endocuff Vision) became the first mechanical device the use of which the FDA acknowledged improved ADRs.

Gross said that it would be interesting to see whether the mechanical devices and artificial intelligence enhancements could complement each other so as to yield even higher detection rates.

Session moderator Brooks Cash, MD, a professor of medicine at the University of Texas Health Science Center, Houston, Texas, said the difference in detection rates made an impressive case for the G-EYE.

"I wouldn't say I'm convinced," Cash told Medscape Medical News. "I'd like to see more data. But I think that the plurality of the evidence that they presented and the size of the study were certainly compelling."

He added that he'd like to see evidence that adding the balloon to a colonoscope doesn’t complicate the cleaning of the device.

Gross has a financial relationship with Olympus, the maker of the Endocuff Vision. Cash reports no relevant financial relationships.

American College of Gastroenterology (ACG) 2021 Annual Scientific Meeting: Presidential plenary session 1, no. 2. Presented Oct. 25, 2021.

Laird Harrison writes about science, health, and culture. His work has appeared in magazines, newspapers, and online publications. He is at work on a novel about alternate realities in physics. Harrison teaches writing at the Writers Grotto. Visit him at or follow him on Twitter: @LairdH.

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