Gastric Sinus Mucosa Indigo Rouge Stain Spray Border Clear is a clear border of the mucosa of the gastric sinus lesion observed when the indigo rouge stain is sprayed in the stomach. Indigo carmine is a non-hazardous mucosal stain that is used in all gastrointestinal examinations. The principle of its action is that it is deposited under gravity in the low concavity of the epithelial surface of the gastrointestinal tract, and the stain can outline the morphology of the gastrointestinal tract, etc., from which the extent and general nature of the lesion can be deduced. During gastroscopy, there are mucosal changes in the gastric sinus, so it is necessary to perform indigo carmine spraying to observe the nature and extent of the mucosal lesions, and the clear borders of the gastric sinus mucosa indigo carmine spraying suggests that the nature of the lesion is not serious, and the diagnosis can be clarified through biopsy and pathologic examination. It is recommended to consult with a professional physician and follow his/her advice.