Abstract
Colonoscopy is considered the 'gold standard' for detection and removal of premalignant lesions in the colon. However, studies suggest that colonoscopy is less protective for right-sided than for left-sided colorectal cancer. Optimizing the effectiveness of colonoscopy is a continuous process, and during the past decade several important quality indicators have been defined that can be used to measure the performance of colonoscopy and to identify areas for quality improvement. The quality of bowel preparation can be enhanced by split-dose regimens, which are superior to single-dose regimens. Cecal intubation rates should approximate 95% and can be optimized by good technique. In selected patients, specific devices can be used to facilitate cecal intubation. Adenoma detection rates should be monitored and exceed a minimum of 25% in men and 15% in women. To this aim, optimal withdrawal technique and adequate time for inspection are of utmost importance. Of all advanced imaging techniques, chromoendoscopy is the only technique with proven benefit for adenoma detection. Finally, the technique of polypectomy affects the number of complications as well as the success of completely removing a lesion. In this Review, we provide an overview of both standard and novel colonoscopy techniques and their impact on quality indicators.
Key Points
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Quality assurance using a minimal set of indicators is essential to continuously improve the effectiveness of colonoscopy
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Split-dose preparation is superior to single-dose preparation for both the quality of preparation and the tolerability
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The use of variable stiffness colonoscopes is associated with a higher cecal intubation rate than are standard colonoscopes
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Of all advanced imaging techniques, panchromoendoscopy is the only one proven to improve adenoma detection
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Cold biopsy polypectomy seems to be associated with a high incomplete resection rate
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E. Dekker has received grant or research support from Olympus and Pentax. Y. Hazewinkel declares no competing interests.
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Hazewinkel, Y., Dekker, E. Colonoscopy: basic principles and novel techniques. Nat Rev Gastroenterol Hepatol 8, 554–564 (2011). https://doi.org/10.1038/nrgastro.2011.141
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DOI: https://doi.org/10.1038/nrgastro.2011.141
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