Proposed Nomenclature and Classification of the Dye-spraying Techniques in Endoscopy

Summary In this short communication, we propose a new nomenclature and classification of dye-spraying techniques in digestive endoscopy. The procedures with dyestuffs which had been reported in diagnostic endoscopy were divided according to actions of the dyesolutions into three methods; ie. Contrast, Biological Staining and Chemical Reaction methods. Recent application of fluorescent dyes to the diagnostic field were also added to the list as the fourth technique. The term "Contrast method" should be applied to a technique for enhancing the relief on the mucosal surface. Indigo Carmine and Evans Blue were available for this method. The second term, "Biological Staining", concerns an effect of vital staining where a dye applied on the mucosa was absorbed through the cellular membrane and stored in the cytoplasm. Several basic dyestuffs, Janus Green B, Neutral Red and Methylene Blue, are usually called "in vivo" staining dyes. When a dye on the mucosal surface reacted with a constituent of the epithelial cell, or with secretion at an adequate pH level, we use the term "Chemical Reaction" method. In this technique, Lugol's solution was applied to the esophageal epithelium and Congo Red to the gastric mucosa. In the practice of dye-spraying in diagnostic endoscopy, a suitable protocol is recommended for recording the instrumentation, medication, dye effect and complications. Complications have never been reported, but any possible long-term biological effect of the dyes had to be closely watched when the examination was repeated.