It refers to the clinical syndrome of duodenal obstruction caused by various reasons, resulting in dilatation of the proximal part of the duodenal obstruction and congestion of chyme. The main symptoms are epigastric pain and fullness, mostly occurring during or after eating, nausea, vomiting bile-like material, and sometimes trying to vomit on their own to relieve symptoms due to epigastric fullness. There are many causes, and the majority of cases (50%) are caused by the superior mesenteric artery compressing the duodenum to form congestion, which is also called superior mesenteric artery syndrome. Other causes are: 1, congenital anomalies; 2, tumors; 3, infiltrative disease and inflammation of the distal or proximal jejunum of the duodenum; 4, adhesions after surgery of the gallbladder and stomach pulling the duodenum, adhesions, ulcers, stenosis or input loop syndrome after gastrojejunostomy; 5, other congenital anomalies: duodenal inversion, duodenal obstruction due to gallbladder duodenal cords, etc. Symptoms: mainly epigastric pain and fullness symptoms, mostly occurring during or after eating, nausea, vomiting bile-like material, sometimes trying to vomit on their own to relieve symptoms due to epigastric fullness. The symptoms are recurrent and gradually worsen. Constipation often occurs. 1.Barium meal examination. Stasis and dilatation signs of duodenum can be seen, or sudden obstruction of barium somewhere in the duodenum, and sometimes retroperistalsis is seen. 2.Gastroscopy. The cause of obstruction in the duodenal lumen and obstruction of gastroscopy at the site of obstruction can be found. 3, fasting extraction of duodenal fluid often. Can be found with food residues, etc. Differentiation: indigestion symptoms need to be differentiated from peptic ulcer, and sometimes both can coexist. Tumors outside the duodenum, such as pancreatic head cancer or giant pancreatic cyst compression causing duodenal stasis, can be differentiated by endoscopy or retrograde cholangiopancreatography. Occasionally, the disease can be caused by compression of the duodenum by abdominal aortic aneurysm. The disease also needs to be distinguished from duodenal obstruction caused by stones, fecal stones, roundworm masses, and foreign bodies in the duodenum. Treatment: Those without obvious symptoms may not need to be treated. Intravenous nutrition including fat emulsions, nasal cannula decompression and antitussive drugs are given during acute attacks to treat acute gastric dilatation. Usually, it is advisable to have small and frequent meals, make knee-chest position for half an hour after meals, and strengthen abdominal muscle exercise. If conservative medical treatment is not obvious, surgical treatment can be used. Surgical options are: 1. free duodenal ligament; 2. duodenojejunostomy; 3. duodenal repositioning.