[Thorotrastoses--viewed in retrospect (author's transl)].

Thorium dioxide (Thorotrast) was used as a contrast medium from 1930 to 1945. It gave excellent contrast and was well tolerated during the application, but due to its radioactivity and its long biological half life it caused various late complications as fibrosis and malignant tumors. The late side effects of the substance are reported on, and the most frequent complication--the induction of hepatomas--is illustrated by two cases.