A comparison of high definition-image enhanced colonoscopy and standard white-light colonoscopy for colorectal polyp detection.

BACKGROUND AND STUDY AIMS

Colonoscopy is widely used to detect and remove precancerous polyps, but fails to detect some polyps. Recent studies evaluating different image-enhanced methods have revealed conflicting results. The efficacy of colonoscopy imaging with simultaneous use of commercially available improvements, including high definition narrow band imaging (HD-NBI), and monochromatic charge-coupled device (CCD) video, was compared with a widely used standard definition white light (SDWL) colonoscopy system for detecting colorectal polyps. The primary aim was to determine whether the combination of image-enhanced colonoscopy systems resulted in fewer missed polyps compared with conventional colonoscopy.

PATIENTS AND METHODS

In a randomized controlled trial (Clinicaltrials.gov. study number NCT00825292) patients having routine screening and surveillance underwent tandem colonoscopies with SDWL and image-enhanced (HD-NBI) colonoscopy. The main outcome measurement was the per-polyp false-negative ("miss") rate. Secondary outcomes were adenoma miss rate, and per-patient polyp and adenoma miss rates.

RESULTS

100 patients were randomized and 96 were included in the analysis. In total, 177 polyps were detected; of these, 72 (41 %) were adenomatous. Polyp and adenoma miss rates for SDWL colonoscopy were 57 % (60/105) and 49 % (19/39); those for image-enhanced colonoscopy were 31 % (22/72) and 27 % (9/33) (P = 0.005 and P = 0.036 for polyps and adenomas, respectively). Image-enhanced and SDWL approaches had similar per-patient miss rates for polyps (6/35 vs. 9/32, P = 0.27) and adenomas (4/22 vs. 8/20, P = 0.11).

CONCLUSIONS

Utilization of multiple recent improvements in image-enhanced colonoscopy was associated with a reduced miss rate for all polyps and for adenomatous polyps. It is not known which individual feature or combination of image-enhancement features led to the improvement.