The opacification of blood vessels for radiographic visualization, long a common diagnostic procedure in Western Europe and Latin America, was not widely adopted in this country until relatively recent years, following the development of direct surgery of the arteries. More frequent intravascular injections of radiopaque substances have been followed by a disturbing increase in reports of serious sequelae.2,3,5,11,13 Some of these untoward reactions have been due to the technique of injection, but most have been properly attributed to the opacification media.1,3
Previously8 we reported our experience with one of the new contrast media, diatrizoate, in about 100 vascular opacifications. Since then we have continued the study with the diatrizoate salts and have made parallel observations with sodium diprotrizoate.
The chemical structures of diatrizoic acid and diprotrizoic acid are similar (Fig. 1).Each is a 2,4,6-triiodobenzoic acid nucleus with an acid amino side-chain in the 3,5-position.