Background. Chromo-endoscopy (dye spraying, endoscopic vital staining) involves different types of dyes used to highlight specific gastrointestinal findings, to enhance the detection of diseased areas and/or to guide biopsies during digestive endoscopy. Dyes are divided into four categories: contrast stains (indigo-carmine), absorptive dyes (Lugol’s solution, methylene blue, toluidine blue, cresyl violet), reactive stains (Congo red, phenol red) and retention pigment (India ink tattooing). Aims of this paper is to review principles of different vital staining used in routine endoscopy based on our own experience. Methods. For the most methods, coloured solution has been sprayed on the mucosa through the operating channel of a standard endoscope using standard catheters (India ink tattooing is done using standard injector). We routinely use methylene blue (for Barrett’s oesophagus diagnostics, including discovering dysplasias and for early colorectal cancers detection), Lugol’s solution (for early oesophageal cancer detection and for Barrett’s oesophagus diagnostics), Congo red (under acidic condition, it changes to a blue-black colour) and indigo carmine (to enhance endosco- pic visualisation and marked highlighting of topographic anatomy). Conclusions: Chromo-endoscopy is a sim- ple, safe, inexpensive, and effective method to better characterise specific mucosal finding during digestive endoscopy. It can be performed in any standard endoscopy unit.

        Key words: Chromo-endoscopy – Lugol’s solution – methylene blue – toluidine blue – cresyl violet – indigo- carmine – Congo red – phenol red – India ink tattooing