Because the suspension offered high image quality and had virtually no immediate side-effects compared to the alternatives available at the time, Thorotrast became widely used after its introduction in 1931 . ( Ant�nio Egas Moniz contributed to its development . ).
22.
Because of this high mass and strong absorption, if alpha-emitting radionuclides do enter the body ( upon being inhaled, ingested, or injected, as with the use of Thorotrast for high-quality X-ray images prior to the 1950s ), alpha radiation is the most destructive form of ionizing radiation.
23.
Known risk factors for cholangiocarcinoma include primary sclerosing cholangitis ( an inflammatory disease of the bile ducts ), infection with the parasitic liver flukes " Opisthorchis viverrini " or " Clonorchis sinensis ", some congenital liver malformations, and exposure to Thorotrast ( thorium dioxide ), a chemical formerly used in medical imaging.
