In the context of a CT scan, what does the term "contrast agent" refer to?

The term "contrast agent" in the context of a CT scan refers specifically to a substance that enhances the contrast of structures or fluids within the body in the images produced. This enhanced contrast improves the differentiation between various tissues and vascular structures, allowing for a more accurate diagnosis. For instance, iodine-based contrast agents are commonly used to highlight blood vessels and organs during imaging, making them more visible on the CT scan.

This enhancement is crucial because many tissues have similar densities and can appear indistinguishable in standard imaging. By using a contrast agent, healthcare professionals can better visualize abnormalities, lesions, or other pathologies that may not be easily detectable without this enhancement. The use of contrast agents significantly contributes to the overall effectiveness and diagnostic capability of CT imaging.