Ultrasound of the abdomen is not particularly ideal for the examination of the intestinal tract. For the intestinal part, abdominal ultrasound can examine the occupying lesions of the intestine, and can more clearly detect the occupying lesions of the stomach tissue or large intestine, such as tumors, polyps and other abnormal growths, but it is not effective in examining other intestinal diseases, such as enteritis, ulcerative colitis and Crohn’s disease. Abdominal ultrasound is mainly used to understand the position and appearance of substantial organs, such as the size and shape of liver, gallbladder, spleen, pancreas, kidney, bladder and other organs, and can check whether the organs are in normal position and whether they are compressed by surrounding tumors or organs. Patients with intestinal problems are advised to undergo colonoscopy and routine stool examination first. Colonoscopy can observe whether there is mucosal tissue congestion, edema and erosion in the intestine, and can also find out whether there are long polyps, intestinal tumors and other abnormal proliferative conditions, which is a more common and accurate way to check gastrointestinal diseases at this stage; stool routine is also one of the common examination methods for digestive system diseases, which can determine whether there is intestinal inflammation, gastrointestinal bleeding or Bacterial dysentery, amoebic dysentery, colorectal cancer, etc.