Surveillance colonoscopy using a transparent hood and image-enhanced endoscopy.

Colonoscopists can miss adenomas during colonoscopy screening. A transparent hood attached to the tip of the colonoscope helps detection of colorectal adenomas, but as far as we are aware, there has been no trial indicating its statistically significant effectiveness. Total colonic dye spray might improve the adenoma detection rate but it is complicated and time-consuming for routine clinical usage. Moreover, the efficacy of narrow band imaging for detection of colorectal adenoma is controversial and is still under debate. Autofluorescence imaging (AFI) might be better able to detect flat lesions than white light imaging (WLI), but its ability is influenced easily by the area of the observation. Therefore, we have attached a transparent hood to the tip of an AFI colonoscope during colonoscopy screening in clinical usage. AFI can detect a flat lesion, which is difficult to detect using WLI. A transparent hood can help to detect lesions behind the folds by pushing the colonic fold. We expect that mounting a transparent hood would work complimentary to AFI. Further improvements, including a combination of AFI and a transparent hood, are needed and they would provide optimal surveillance intervals.