The part of the human body below the chest and above the stomach, which is clinically known as the upper abdomen, is mainly the abdominal cavity, and the tissues and organs in the abdominal cavity mainly include the liver, gallbladder, bile ducts, pancreas, spleen, stomach, and transverse colon. Therefore, in case of clinical discomfort in the upper abdomen, the first consideration is upper gastrointestinal tract disease or hepatobiliary system disease. Preferred non-invasive tests, such as hepatobiliary ultrasound or CT examination, can clearly understand the presence of stones or liver tumors. If there is no obvious abnormality after the above examination, even further gastroscopy is needed if necessary to clarify whether there is a combination of superficial gastritis or peptic ulcer, or in severe cases, it may be a stomach tumor. Therefore, the main organs in the upper abdomen are the gastrointestinal tract, that is, stomach, duodenum, liver and gallbladder, pancreas and spleen.