The obstruction of food passage in the stomach is due to lesions such as ulcers or cancerous tumors. It can be divided into two main categories: incomplete obstruction and complete obstruction. Pyloric obstruction is one of the common complications of gastric and duodenal ulcers and can occur in the recent (i.e., active) or late stage of ulcer disease. The pylorus is the narrowest part of the digestive tract, with a normal diameter of about 1.5 cm, and is therefore prone to obstruction. Due to the obstruction of the pylorus passage, gastric contents cannot enter the intestine smoothly and are retained in the stomach in large quantities, resulting in hypertrophy of the muscular layer of the gastric wall, enlargement of the gastric lumen and inflammation, edema and erosion of the gastric mucosal layer. Clinically, the patient is unable to eat normally for a long time and vomits a lot, resulting in severe malnutrition, hypoproteinemia and anemia, and water and electrolyte disorders such as severe dehydration, hypokalemia and alkalosis. Diagnosis of impaired passage of food in the stomach due to gastric ulcer: 1. The clinical manifestations of gastric ulcer have 3 characteristics: ① chronic course: less than a few years, more than 10 years or longer. ② Periodicity: the course of the disease often has alternating periods of attack and remission. ③Rhythmical: the pain manifests itself as postprandial pain, which starts half an hour after a meal and disappears until the next meal, week after week. The symptoms of gastric ulcer are mainly manifested as abdominal pain; with or without vomiting, nausea, acid reflux, belching and other symptoms. However, there are many patients with various complications of gastric ulcer such as perforation, bleeding, pyloric obstruction and as the first symptom. 2, epigastric pain and discomfort: the pain of gastric ulcer is a visceral nature of pain, the body surface is not exactly localized, while the pain is not intense, can be tolerated, manifested as burning pain, vague discomfort, etc.. The active phase is rhythmic, manifesting as postprandial pain, with cyclic and seasonal characteristics as the pathology develops. Ulcers near the cardia can also manifest as burning sensation behind the sternum and left chest pain. When the ulcer penetrates, it is manifested as increased pain, radiating to the back or back pain, along with nocturnal pain and other manifestations. When the nature and rhythm of pain changes, the possibility of malignant transformation should also be alerted. 3, nausea, vomiting: no pyloric obstruction and vomiting mostly indicates that the ulcer is in the active stage, vomiting is intermittent. Frequent vomiting mostly indicates pyloric obstruction. 4. Acid reflux, belching, diarrhea: Acid reflux also indicates that the ulcer may be in the active stage. 5, bleeding, perforation: bleeding, perforation have their own special clinical manifestations, see the section on complications.