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How can radiation be used to diagnose and treat disease?

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The environmental effects of nuclear radiation — radiation The harmful effects of radiation from nuclear bombing.

Radiation is a cornerstone of modern medicine, utilized extensively for both diagnostic imaging and therapeutic treatment.1

Diagnostic Applications

Radiation enables physicians to visualize internal structures without invasive surgery.2
* X-ray Systems: These use electromagnetic radiation to create images based on differential absorption; denser tissues like bone absorb more radiation, appearing lighter on film.23
* Computed Tomography (CT): By rotating X-ray beams around a patient, CT scans produce detailed cross-sectional images, allowing for precise localization of abnormalities.2
* Nuclear Medicine: This field uses radioactive isotopes as tracers. Because these isotopes behave chemically like stable elements, they can be tracked within the body to monitor physiological processes, such as thyroid activity or organ structure.43

Therapeutic Applications

Radiation therapy, or radiotherapy, uses ionizing radiation—such as X-rays, gamma rays, or subatomic particles—to destroy cancer cells.5
* Mechanism: Radiation damages the DNA of rapidly proliferating cancer cells, preventing them from replicating or inducing programmed cell death (apoptosis).5
* Delivery: Techniques include teletherapy (external beams) and brachytherapy (internal placement of radioactive sources directly into or near a tumor).5

While highly beneficial, radiation carries risks, and medical professionals carefully balance these against the therapeutic necessity of each procedure.67