Contrast agents

Contrast agents are an essential part of radiology, with a percentage of use ranging from 100% in procedures such as angiography to less than 1% in present ultrasound imaging. The sections of this report review the literature on contrast agents used for the three main imaging modalities: x-ray, magnetic resonance imaging (MRI), and ultrasound. Special focus has been given to the safety of the media, particularly with regard to neural tolerance. Each section is divided into a short introduction on the history of this type of media, a review of their characteristics, and possible future developments. The different types of contrast media are reviewed in order of their historical development: first x-ray contrast agents, then MRI, and lastly, ultrasound contrast media.