Some patients have gallstones, but the gallstones are gone during the later review. There may be other factors, including small gallstones that have been discharged into the intestine under the contraction and diastole of the bile duct, and the patient may have transient pain during the discharge process, or the symptoms may not be obvious. In another case, the gallstones enter the bile ducts but do not cause inflammatory irritation and produce symptoms. If an MRI is performed at this time, it may indicate stones in the common bile duct but not in the gallbladder. In older patients, there may be a dysfunction of the biliary sphincter, and the stones in the gallbladder enter the intestine through the dysfunctional sphincter.