[Rational procedures in the differential diagnosis of jaundice].

In jaundice after exclusions of prehepatic and functional hepatogenic hyperbilirubinaemias the sonography should pre-eminently be used as a riskless, economical and qualified investigation method, taking into consideration clinical and laboratory-chemical data. If sonographically the findings of an intrahepatic cholostatis are shown, in therapeutic relevance the histological clarification must follow. Only in unequivocal focal changes of the liver (perhaps thin needle puncture) further investigations are unnecessary. If there are findings of an extrahepatic cholostasis, in a not unequivocal sonographic result or before a surgical intervention further aimed investigations, such as ERCP, PTC and CT, are necessary for the exact clarification of the cause of the obstruction of the bile ducts.