Also referred to as contrast agent or contrast medium. Any internally administered substance that has a different opacity from soft tissue on radiography or computed tomography. Includes:
- Barium or water, used to make parts of the
gastrointestinal tract opaque.
- Iodine in water, used for arthrography.
- Water soluble iodine, used to make blood vessels opaque; to demonstrate the inner structures of the urinary tract (kidneys, ureters and bladder); and to outline joints (the spaces between two bones).
- Iodine mixed with water or oil may be used to evaluate the fallopian tubes and lining of the uterus.
- Sterile saline (salt water) is used during hysterosonography.
- May refer to air occurring naturally or introduced into the body.
- Paramagnetic substances used in magnetic
For more information see the Contrast Meterials page.