Radiopaque Contrast Agents

Glossary Term:

Radiopaque Contrast Agents

Definition

Materials that stop or attenuate radiation that is passed through the body, creating an outline on film of the organ(s) being examined. Contrast agents, sometimes called "dyes," do not contain radioisotopes. When such agents are used, exposure to radiation results only from the X-ray equipment used in the examination. The chemical structure of radiopaque contrast agents can produce a variety of adverse reactions, some of which may be severe — and possibly life-threatening — in certain individuals.