Roentgen Visualization of Liver and Spleen With Thorium Dioxide Sol

Since Radt's 1 original publication in 1929 of his work on visualization of the liver and spleen with a colloidal suspension of thorium dioxide (now marketed under the trade name of Thorotrast) injected intravenously, numerous reports have been published in both the American and the foreign literature on almost every phase of this problem. Until Radt's work, methods of examination of the liver and spleen were limited to very gross means of determining its size through indirect methods such as palpation, roentgen examination of the colon, and pneumoperitoneum. There were no means of demonstrating structural changes within these organs. The spleen and liver had been visualized in animals while other problems were being worked on, but with lethal results. 2 Radt, first working with animals and later with human beings, was able to visualize the liver and spleen and demonstrate gross changes very beautifully with a fine colloidal suspension of