Gallbladder ultrasound examination can not eat, need to fasting, and fasting time should reach more than 8 hours, some patients with poor digestive function, the night before doing gallbladder ultrasound examination should not eat too late, do not eat too greasy, do not eat too much meat, soy products and other food. If you eat, the gallbladder contracts, the bile empties and the gallbladder cavity becomes smaller, which affects the diagnosis of gallbladder disease. The diagnosis of cholecystitis can only be made if the gallbladder is well filled. Generally, the gallbladder wall will thicken and the gallbladder diameter will increase in cholecystitis. A well-filled gallbladder can better show gallbladder polyps, adenomyosis, gallbladder tumors and other diseases.