Late Effects of Thorotrast in Tissues

Abstract

Case history of a 53-year-old woman who developed a painful firm mass in the cubital region which on the roentgenogram resembled myositis ossificans. She had received a thorotrast injn. for diagnostic purposes 12 yrs. previously. Radioactivity in the cubital region was ascertained by means of Geiger-Muller counter. Biopsy showed a dense acellular fibrous tissue reaction around extravascular granules (thorium dioxide). Radio-autographs showed that these granules were the birth place of alpha particle tracks.