As of the latest update, Google Chrome and Microsoft Edge have made a breaking change to how file uploads are handled. Once your system installs this update, you will not be able to upload new images. Please use another browser until we can get it fixed.


Dr Rohit Sharma and Radswiki et al.

Thorotrast is a suspension of radioactive thorium dioxide first produced in Germany in 1928 and used as a contrast agent until the 1950s. Its principal use was for cerebral angiography: 90% of the estimated 50,000-100,000 patients treated received it for this purpose. Umbrathor was another thorium dioxide-based contrast medium which was principally used for assessment of the GI tract.

Thorotrast was an alpha emitter, which was retained by the body, a combination which make it highly carcinogenic. The deposition of Thorotrast was dependent on its radiological use, preparation method, and the age of the preparation. The primary site of deposition was the reticuloendothelial system including the liver, spleen, bone marrow, and lymph nodes.

In patients treated with Thorotrast, a plain radiograph of the abdomen demonstrates fine, irregular metallic densities distributed throughout the liver, spleen, and peripancreatic lymph nodes 4

Hepatic angiosarcoma is the classic Thorotrast-related neoplasm. Other associated cancers include:

Share article

Article information

rID: 12721
Synonyms or Alternate Spellings:
  • Thorotrast contrast
  • Thorium dioxide contrast

Support Radiopaedia and see fewer ads

Cases and figures

  • Case 1
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.