"Contrast" is a term describing the substances used to help improve the visualization of internal body structures. We use several different types of contrast:

Iodine based
This type of contrast is usually injected into a vein so it can disperse throughout the organs of the body, enhancing their appearance. Occasionally, iodine-based compounds are given orally or through an enema. Many CT exams - intravenous pyelograms, angiograms and venograms - require this type of contrast. If you are 65 or older or have diabetes or kidney function problems, please consult your physician so a simple blood test can be done before your exam.

Barium
Barium is an element that is mixed into a liquid form and is given orally and/or through an enema. Barium helps to highlight the gastrointestinal system.

Air
Air is often used in addition to barium as a contrast agent for examinations of the gastrointestinal system.