Emergency Body CT > Technique > IV Contrast


IV Contrast

A large number of iodinated contrast agents are available that can be divided into three basic classes:

1) High osmolar contrast agents--"ionics"
2) Low osmolar contrast agents--"non-ionics"
3) Iso osmolar contrast agents (like Visipaque - Iodixanol)

All the agents contain an iodinated benzene ring derivative. The ionic contrast agents such as Diatrizoate (e.g. Hypaque and Renograffin) are typically formulated as sodium and/or meglumine salts. These agents cost less than the non-ionic class; however, they are rarely used now because they have a 6-9 times greater incidence of adverse reactions.

Non-ionic contrast agents like Iohexol (e.g. Omnipaque) are used exclusively at many institutions due to their decreased side effects (nausea, flushing, and shortness of breath). Iodixanol is a dimer. Isoosmolar contrast may have a renoprotective effect on diabetics with renal failure.

The decision to use iodinated contrast should be made on a case by case method, and the risks and benefits carefully considered in light of the clinical condition, patient stability and GFR (if available).

 

© Copyright Rector and Visitors of the University of Virginia 2013