Meningioma Induced by Thorium Dioxide

Abstract

THORIUM dioxide (Thorotrast) was introduced as a contrast medium for cerebral angiography by Egas Moniz et al.1 in 1931. Its instillation into the subarachnoid space and ventricles for encephalomyelography was described in the following year by Radovici and Meller.2 , 3 This contrast medium, containing thorium, with a half-life of 1.4 X 1010 years, was employed extensively for many years, despite the potential hazard from subsequent lifelong radiation. Its use has been almost completely abandoned, however, since its implication in the pathogenesis of a variety of carcinomas, sarcomas and endotheliomas.4 , 5 The present report provides an additional example of tumor formation in the . . .