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X-ray

X-ray is an imaging technique that has been used since 1895 to show up abnormalities in bones and certain body tissue, such as breast tissue.

X-rays are a type of high-energy radiation that is like light waves but higher in energy. An x-ray machine can produce short bursts of x-rays that pass easily through fluids and soft tissues of the body but are blocked by dense tissue such as bone.

Contrast x-rays use a substance (called a contrast medium) that makes hollow or fluid-filled structures visible. This means that structures such as the digestive tract, blood vessels or urinary system that do not usually show up on x-ray, can be seen. The substance is injected or swallowed and X-rays cannot pass through it, so the area will appear white on the x-ray.