Comparison of painless, ultrafine and ordinary gastroscope endoangel-assisted blind spots: a prospective, single-blind, three-group, randomized, single-center trial

INTERVENTION: 6 groups:EndoAngel; CONDITION: Rate of Blind Spot in Gastroscopy PRIMARY OUTCOME: Blind spot rate; SECONDARY OUTCOME: Blind spot rate;Operation time;Comfort degree;Limb coordination;Vomiting reaction; INCLUSION CRITERIA: 1) Males or females aged at least 18 years; 2) Gastroscopy is needed to further clarify the characteristics of digestive tract diseases; 3) Painless, ordinary and ultra‐fine gastroscopy patients; 4) Able to read, understand and sign informed consent; 5) The investigator believes that the subjects can understand the clinical research process, are willing and able to complete all the research procedures and follow‐up visits, and cooperate with the research procedures.