[Ultrasound in differential diagnosis of intrahepatic and extrahepatic cholestasis (author's transl)].

116 patients with clinically suspected obstructive jaundice were subjected to primary sonographic examination by means of the "real-time" method to differentiate between intrahepatic (internal) and extrahepatic (surgical) cholestasis. Diagnosis was finally confirmed by observing the clinical course, by further examinations, and in 63 cases by surgery or PM. Sonographic examination revealed the direct cause of the extrahepatic obstruction in 82 of 87 patients (94.3%) with extrahepatic cholestasis; in case of dilatation of the bile duct, the approximate site of the obstruction could be determined. In about 75% of the cases, the cause of biliary obstruction was correctly identified. Intrahepatic tumours or metastases were present in 10 of 27 patients with intrahepatic cholestasis; sonographic identification was effected in all cases and histologically or cytologically confirmed with aspiration material from fine-needle biopsies. The high accuracy and uncomplicated technique avoiding discomfort or harm to the patient, make sonography a useful method in differential diagnosis of cholestasis.