Why Do Iodine and Barium Enhance CAT Scans

The innovative and technological achievement of computerized axial tomography required a sophisticated understanding of physiology, mathematics, and radiology. A clear comprehension of chemical principles also contributes to the success of this diagnostic technique. 

What can one do to image specific soft tissues using X-rays One must enhance the density of these regions to decrease the ability to transmit X-rays through the region. To aid in the creation of such images or CAT scans, contrast media are often ingested or injected into the body. Contrast medium fluids that are opaque (i.e., not transparent) to X-rays are known as radiopaque media. These 

Why are barium- and iodine-based materials selected for contrast media The production of X-ray images depends on the differences between the X-ray absorbing power of various tissues. This difference in absorbing power is called contrast and is directly dependent on tissue density. To artificially enhance the ability of a soft tissue to absorb X-rays, the density of that tissue must be increased. The absorption by targeted soft tissue of aqueous solutions of barium sulfate and iodized organic compounds provides this added density through the heavy metal barium and the heavy nonmetal iodine. 

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