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. 2012 Jul;2(3):114-119.
doi: 10.4161/jig.23730. Epub 2012 Jul 1.

A new method for screening and surveillance colonoscopy: Combined water-exchange and cap-assisted colonoscopy

Andrew W Yen  1 , Joseph W Leung, Felix W Leung
Affiliations

A new method for screening and surveillance colonoscopy: Combined water-exchange and cap-assisted colonoscopy

Andrew W Yen et al. J Interv Gastroenterol. 2012 Jul.

Abstract

Background & aims: Colonoscopy plays an important and central role in current colorectal cancer screening and prevention programs, but it is an imperfect tool. Adjunct techniques may help improve the performance of colonoscopy to increase the detection of polyps with neoplastic potential. This study investigates the novel approach of combined water-exchange and cap-assisted colonoscopy (WCC) and its impact on adenoma detection.

Methods: A single-center single-colonoscopist consecutive group observational study to compare WCC with conventional air insufflation colonoscopy was performed. Data were collected from 50 consecutive patients undergoing outpatient colorectal cancer screening or polyp surveillance with WCC. Adenoma detection rates (ADR) and adenomas detected per colonoscopy (APC) were compared to a control group of 101 consecutive patients examined with conventional air colonoscopy during the immediate prior period.

Results: Cecal intubation was achieved in all patients. As an emerging and alternative quality metric for colonoscopy, APC was significantly higher in the WCC group (3.08 vs. 1.50, p=0.0021). The conventional quality metric, overall ADR, was higher in the WCC group compared to the air colonoscopy group (70.0% vs. 59.4%, p=0.22). This difference was not statistically significant, likely due to a type II error.

Conclusion: The observational data suggest APC is a more sensitive indicator of quality colonoscopy than ADR. WCC shows promise as a novel technique that merges two simple adjunct methods to help improve the performance of colonoscopy. The data suggest larger, prospective studies are necessary to determine the true impact of water-exchange combined with cap-assisted maneuvers.

Keywords: adenoma; cap-assisted colonoscopy; colon cancer; colonoscopy; screening; water colonoscopy.

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Figures

Figure 1
Figure 1
Disposable Distal Attachment (D-201-12704, Olympus Medical Systems Corp., Tokyo, Japan)
Figure 2
Figure 2
Underwater endoscopic view of the appendiceal orifice (A) and terminal ileum (B) with the cap mounted scope. Note, the distal attachment is nearly transparent underwater.
Figure 3
Figure 3
Cecal polyp seen with cap mounted colonoscope
See this image and copyright information in PMC

References

    1. American Cancer Society, author. Cancer Facts & Figures 2012. Atlanta: American Cancer Society; 2012.
    1. Winawer SJ, Zauber AG, Ho MN, O'Brien MJ, Gottlieb LS, Sternberg SS, et al. Prevention of colorectal cancer by colonoscopic polypectomy. The National Polyp Study Workgroup. N Engl J Med. 1993;329:1977–1981. - PubMed
    1. Zauber AG, Winawer SJ, O'Brien MJ, Lansdorp-Vogelaar I, van Ballegooijen M, Hankey BF, et al. Colonoscopic polypectomy and long-term prevention of colorectal-cancer deaths. N Engl J Med. 2012;366:687–696. - PMC - PubMed
    1. Stock C, Dianne Pulte D, Ulrike Haug U, Hermann Brenne H. Subsite-specific colorectal cancer risk in the colorectal endoscopy era. Gastrointest Endosc. 2012;75:621–630. - PubMed
    1. Cooper GS, Xu F, Barnholtz Sloan JS, Schluchter MD, Koroukian SM. Prevalence and predictors of interval colorectal cancers in Medicare beneficiaries. Cancer. 2012;118(12):3044–3052. - PMC - PubMed