Organic iodine compounds attenuate x-rays as they pass through the body, thereby allowing the body structures containing iodine to be delineated in contrast to those structures that do not contain iodine. The degree of opacity produced by these compounds is directly proportional to the total amount (concentration and volume) of the iodinated contrast agent in the path of the x-rays. After intravascular administration, iodixanol makes opaque those internal structures in its path of flow, allowing their visualization until significant hemodilution and elimination occur.
Iodixanol is a contrast agent commonly used during coronary angiography, particularly in individuals with renal dysfunction, as it is believed to be less toxic to the kidneys than most other intravascular contrast agents. It is an iso-osmolar contrast agent, with an osmolality of 290 mOsm/kg H20, the same as blood.
Non-ionic radiocontrast agents like iodixanol are cytotoxic to renal cells. The toxic effects include apoptosis, cellular energy failure, disruption of calcium homeostasis, and disturbance of tubular cell polarity, and are thought to be linked to oxidative stress.