Background: Traditional white-light endoscopy cannot reliably distinguish between small (<10 mm) adenomatous and hyperplastic colon polyps. High-definition white-light (HDWL) endoscopy and i-Scan may improve in vivo characterization of small colon polyps.
Objective: To compare HDWL endoscopy and HDWL plus i-Scan for the assessment of small colon polyps and to measure performance against the American Society for Gastrointestinal Endoscopy (ASGE) thresholds for assessment of diminutive colon polyps.
Design: Prospective cohort study.
Setting: Single academic hospital.
Patients: Patients undergoing bowel cancer screening colonoscopy.
Intervention: In vivo assessment of all polyps <10 mm by using HDWL and i-Scan image enhancement.
Main outcome measurements: The primary outcome measure was overall diagnostic accuracy of in vivo assessment of colon polyps <10 mm. Secondary outcome measures were sensitivity and specificity for adenomatous histology, negative predictive value for adenomatous histology of diminutive rectosigmoid polyps, and accuracy of prediction of polyp surveillance intervals.
Results: A total of 209 polyps in 84 patients were included. There were no significant differences between HDWL endoscopy and i-Scan in characterization of polyps <10 mm (accuracy 93.3% vs 94.7%; P = 1.00; sensitivity 95.5% vs 97.0%; P = .50; specificity 89.3% vs 90.7%; P = 1.00). The negative predictive value for adenomatous histology of diminutive rectosigmoid polyps was 100% with both HDWL endoscopy and i-Scan. U.K. and U.S. polyp surveillance intervals were predicted with 95.2% accuracy with HDWL endoscopy and 97.2% accuracy with i-Scan.
Limitations: Single-center study.
Conclusion: HDWL endoscopy may be as accurate as HDWL with i-Scan image enhancement for the in vivo characterization of small colon polyps. Both modalities fulfil the ASGE performance thresholds for the assessment of diminutive colon polyps. (
Clinical trial registration number: NCT01761279.).
Keywords: AGA; ASGE; American Gastroenterological Association; American Society for Gastrointestinal Endoscopy; BSG; British Society of Gastroenterology; CE; DCP; FICE; Fujinon intelligent color enhancement; HD; HDWL; NBI; PIVI; Preservation and Incorporation of Valuable Endoscopic Interventions; SCP; SE; TE; contrast enhancement; diminutive colon polyp; high-definition; high-definition white-light; narrow-band imaging; small colon polyp; surface enhancement; tone enhancement.
Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.