Computed tomography in obstructive jaundice. Part II: The cause of obstruction.

The value of computed tomography (CT) in determining the cause of obstructive jaundice in 67 proved cases is described. The presence of stones, the level of obstruction, the relative size of the ringlike structures produced by the dilated bile duct, and the shape of the distal visualized ring have proved to be the most important variables. The retrospective analysis determined the correct cause in 94% of the cases. CT fulfills all goals considered important in obstructive jaundice and eliminates the need for invasive procedures in many cases.