Contrast agents are substances used in medical imaging techniques such as MRI, CT scans, and X-rays to improve the visibility of internal structures and organs. These agents work by increasing the contrast between different tissues or fluids in the body, making it easier for healthcare professionals to identify and diagnose potential health issues. Contrast agents can be administered orally, intravenously, or directly into the area being examined, and are typically composed of iodine, barium, or gadolinium. They play a critical role in enhancing the diagnostic accuracy of various imaging procedures and are widely used in medical practice.