Usefulness of indigo carmine. (a) Disruption of the mucosal fold and a slightly reddish area are observed, but the whole lesion is unclear. (b) After spraying with indigo carmine dye, a 7 mm depressed lesion (0–II c) is identified clearly. (c) A slightly elevated lesion with an obscure superficial vascular component is evident, but the whole lesion is not recognized. (d) A slightly elevated lesion measuring 18 mm is obviously detected using indigo carmine.
