Dilatation of the small intestine is an important manifestation of malabsorption syndrome, mostly in the jejunum, especially in the lower and middle part of the jejunum, and can sometimes cause dilatation of the entire small intestine, including the duodenum. The degree of small bowel dilatation is related to the severity of the disease, and the cause of dilatation is low tone of the small intestine. It is believed that a small bowel diameter greater than 31 mm can be considered dilated, and the bowel diameter can be two to three times the normal size when it is significantly dilated. Inflation of the small intestine can be mild or severe, while the majority of colonic inflation is more pronounced, often manifesting as peritoneal inflation of the entire colon frame. The distribution of small intestine inflation is mostly in the middle abdomen within the colonic frame, and when the dilatation is severe, the intestinal loops are in the form of continuous tubes; when the dilatation is mild, it appears as separated inflated intestinal tubes. Diagnosis of small intestine dilatation and inflation: small intestine injury: small intestine occupies the largest position in the abdominal cavity, has a wide distribution, is relatively superficial, and lacks the protection of bones and is easily injured. The rate of small bowel injury accounts for 25% to 30% in open injuries and 15% to 20% in closed injuries. When any injury to the abdomen needs to be explored, the examination of small bowel injury should be carried out carefully, meticulously and regularly. Small intestine bacterial overgrowth: malabsorption syndrome occurs in the elderly, mainly related to degenerative changes in the digestive system of the elderly. These changes make the small intestine bacterial overgrowth, diverticulitis and diverticulosis of the digestive tract significantly higher, coupled with degenerative changes that cause insufficient caloric intake and nutritional imbalance, can contribute to or aggravate malabsorption syndrome. Low small bowel obstruction: A clinical manifestation of intestinal obstruction. Intestinal obstruction (ileus) refers to the obstruction of the passage of intestinal contents in the intestine. The clinical manifestations of colonic obstruction are similar to those of low-grade small bowel obstruction, but X-ray abdominal plain examination can distinguish small bowel obstruction as an inflatable intestinal collaterals throughout the abdomen with more fluid level, while the colon does not show, and in the case of colonic obstruction, dilated colon and pouch-shaped small intestine with pneumatization around the abdomen are not obvious.