Intolerance to a fatty diet is one of the symptoms of postcholecystectomy syndrome (PCS), with half of PCS patients experiencing abdominal pain or “dyspepsia” (a feeling of fullness in the upper or right side of the abdomen, abdominal rumbling, nausea, vomiting, constipation, fat intolerance, or diarrhea) within a few weeks after surgery, and the other half within months or years after surgery. diarrhea, etc.) within a few weeks after surgery, and the other half of patients develop symptoms within months or years after surgery. These symptoms are nonspecific and vary depending on the underlying etiology, but often include pain in the right upper abdomen or epigastrium, mostly after meals, and are sharp. So, what tests should be done if the patient is intolerant to a fatty diet? The following is a brief description: 1, biochemical examination: white blood cell count, blood and urine amylase, liver function, glutamate transaminase, γ-glutamyl transpeptidase, etc. are helpful for the diagnosis of biliary obstruction. 2.Intravenous cholangiography: the intrahepatic bile ducts are poorly visualized, and the extrahepatic bile ducts are not clear, and are greatly affected by liver function, so the diagnostic value is not great. 3.B-type ultrasound: it can detect bile duct dilatation, gallstones, biliary tumors, pancreatitis and so on. It is simple, rapid and has some diagnostic value, but it has limitations and cannot show the whole picture and all the signs of the biliary system. 4.Upper gastrointestinal tract imaging: It is helpful to diagnose esophageal hiatal hernia, ulcer disease, duodenal diverticulum, etc. 5.Hepatobiliary CT scan: diagnose liver tumor, intra- and extra-hepatic bile duct dilatation, gallstone disease, chronic pancreatitis, etc. 6.Isotope 99mTc-HDA hepatobiliary scan: to observe dilated intra- and extra-hepatic bile ducts, gallstone disease and liver lesions, function of gallbladder, etc. The method is simple, non-damaging and suitable for patients with jaundice.