The gallbladder size 5.8×2.1cm belongs to gallbladder atrophy if it is the result of fasting, and it is not gallbladder atrophy if it is the result of postprandial. 1. Not gallbladder atrophy: Generally speaking, under normal circumstances, the length of the gallbladder should be 5~8cm and the width should be 3~5cm, if the postprandial state, it is normal. 2. belonging to the gallbladder atrophy: gallbladder size 5.8×2.1cm, if the result of fasting, there is a possibility of gallbladder atrophy. It may be caused by cholecystitis. Cholecystitis is a chemical inflammation caused by gallstones, inflammation and edema of the gallbladder duct, roundworms and other causes of obstruction of the gallbladder duct, bile stagnation and concentration, and stimulation of the gallbladder, and the patient will have shrinkage of the gallbladder. Based on the result of gallbladder size 5.8×2.1cm examination alone, the diagnosis cannot be made accurately, and it is necessary to combine the characteristics of medical history and other examination results to make accurate judgment.