A review of image-enhanced endoscopy in the evaluation of colonic polyps

Abstract

The practice of colonoscopy has changed considerably over the last decade. The growth of image-enhanced endoscopy have altered our concepts of how we perform colonoscopy. This article examines the evidence base behind these techniques and looks at where future research needs to be directed.

Keywords::

• colonic polyp
• FICE
• indigo carmine
• i-scan
• NBI

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Indigo carmine or methylene blue chromoendoscopy increases adenoma detection during routine colonoscopy.

• Indigo carmine or methylene blue chromoendoscopy is the method of choice for the surveillance of patients with ulcerative colitis.

• Indigo carmine or methylene blue chromoendoscopy is an effective tool for in vivo histology prediction of colonic polyps.

• Narrow band imaging (NBI) and flexible spectral imaging color enhancement (FICE) have no role in polyp detection in a surveillance population. The position with i-scan is less clear. There is very little evidence in a high-risk population, with a small selection of studies on NBI and i-scan suggesting they may be of some benefit in increasing the polyp detection rate.

• There is a lack of evidence to recommend NBI, FICE or i-scan for surveillance of ulcerative colitis.

• There is good evidence for the use of NBI, FICE and i-scan for the in vivo histology prediction of colonic polyps.

• The adoption of a ‘resect and discard’ policy for colonic polyps may well be a very cost-effective measure with minimal clinical consequences in expert hands.