Liver ultrasound requires an empty stomach, so try not to eat foods such as soy products that are too oily or produce too much gas the night before. Because the gallbladder needs to be fasted during the examination, if you eat, the bile is emptied, the diagnosis of the gallbladder disease examination will be affected, and the food in the gastrointestinal tract produces gas, which affects the examination of the posterior pancreas. It affects the examination of the liver, and the ultrasound will reflect back after encountering the gas, and the examination of the liver tissue and pancreatic tissue in the rear will be affected.