Cholecystitis is divided into acute cholecystitis and chronic cholecystitis. The imaging manifestations of acute cholecystitis mainly include significant increase in gallbladder volume, thickening and edema of the gallbladder wall, and the presence of fluid in the gallbladder fossa, which may flow into the abdominal cavity in severe cases and cause inflammatory reactions in the surrounding organs. Patients with acute cholecystitis have an acute onset and present with acute abdominal pain accompanied by fever; chronic cholecystitis is usually asymptomatic and is found incidentally during physical examination or when patients present with persistent chronic pain and are seen at the hospital. Since the gallbladder is an organ for storing bile, bile fills the gallbladder during fasting and dilates the gallbladder, which can facilitate accurate observation of the cystic cavity and cystic wall lesions. Therefore, patients need to fast during imaging examinations of gallbladder disease.