High resolution colonoscopy with chromoscopy versus standard colonoscopy for the detection of colonic neoplasia: a randomized study

Clin Gastroenterol Hepatol. 2006 Mar;4(3):349-54. doi: 10.1016/j.cgh.2005.12.009.


Background & aims: High-resolution colonoscopy with chromoscopy (HRC) is a technique designed to improve the detection of colonic neoplasias. We prospectively compared standard colonoscopy (SC) and HRC in a randomized multicenter trial.

Methods: Patients (n = 203; age, 58 +/- 10 years; sex ratio, 1) were recruited according to the following criteria: (1) a history of either familial or personal colonic neoplasia or (2) alarm symptoms after the age of 60 years. After randomization, an SC was performed in 100 patients (resolution, < or = 410,000 pixels) and a HRC in 103 patients (Fujinon EC485ZW, 850,000 pixels). In the HRC group, each colonic segment was examined before and after spraying with indigo carmine 0.4%.

Results: Two hundred seventy-six polyps were detected in 198 patients. One hundred sixty of them were hyperplastic polyps, 116 were adenomas, and 2 were carcinomas. The numbers of hyperplastic polyps and purely flat adenomas were significantly higher in the HRC group than in the SC group (1.1 +/- 1.6 vs 0.5 +/- 1.4 and 0.22 +/- 0.68 vs 0.07 +/- 0.29, respectively; P = .01 and P = .04), but there was no significant difference in the total number of adenomas per patient (primary end point) detected between the HRC and the SC groups (0.6 +/- 1.0 vs 0.5 +/- 0.9, respectively).

Conclusions: Although HRC improves detection of purely flat adenomas and hyperplastic polyps, the overall detection of colonic adenomas in a population at increased risk of neoplasia is not significantly improved. These findings do not support the routine use of HRC in clinical practice.

Publication types

  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoma / pathology*
  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma / pathology*
  • Colonic Neoplasms / pathology*
  • Colonic Polyps / pathology*
  • Colonoscopy / methods*
  • Coloring Agents
  • Female
  • France
  • Humans
  • Image Enhancement
  • Indigo Carmine
  • Male
  • Middle Aged
  • Prospective Studies


  • Coloring Agents
  • Indigo Carmine