Accuracy of sonography and transhepatic chloangiography in obstructive jaundice.

Fifty patients with obstructive jaundice were studied by both ultrasonography and percutaneous transhepatic cholangiography (P)TC). Comparison was made of the relative accuracy of sonography and transhepatic cholangiography in delineating both the site and cause of the jaundice. The site of obstruction was defined in 86% by sonography and in 100% by PTC. Etiology was defined in 52% by sonography and in 86% by PTC. Using both modalities the etiology was evident in 94% of patients. Percutaneous transhepatic cholangiography should be reserved for those patients in whom sonography does not identify the site and cause of the obstruction.