Final answer:
Contrast is used to enhance the visibility of blood vessels, tumors, inflammation, and other structures in medical imaging, aiding in diagnosis and treatment planning. Agents like MRI contrast can provide a clearer picture of soft tissues, and techniques like the EPR effect help target tumors.
Step-by-step explanation:
Contrast improves the visibility of various structures and conditions within the body, which include:
- Blood supply of some organs
- Blood vessels
- Tumors
- Inflammation
- Air-filled spaces
Improving contrast in medical images, such as MRI, PET scans, and other imaging techniques, allows doctors to obtain more detailed visual information. This is crucial in the diagnosis and monitoring of diseases. For example, MRI contrast agents can alter the magnetic properties of water in cells, leading to enhanced images of soft tissues. The EPR effect allows for the passive targeting of nanosystems to tumors due to the abnormalities in their microvasculature. Inflammatory areas and blood vessels become more apparent in scans when there is an increased contrast, which helps in accurate diagnosis and treatment planning. Similarly, PET scans provide insights into the blood flow and metabolic activity of organs, which is invaluable in detecting a range of conditions.