How does an x-ray work?

Plain film radiography unifies principles of photography, anatomy, and x-ray production. X-rays are produced by applying an electric potential across a tube, where electrons are "boiled off" a cathode filament. This electron stream strikes a rotating, positively charged target, the anode. The spinning sound one can often hear during the x-ray study is the rotation of the anode. When the electrons slow down, and when they strike the target, x-rays are produced. A person cannot feel, taste, or see the x-rays as they pass through the body.

The amount and type of x-rays are selected by the operator, usually the radiologic technologist (RT), who adjusts exposure and beam quality. Pre-set ranges are based on the patient thickness, the tissue being imaged, and the desired image contrast. Because motion of the lungs and diaphragm blurs the image -- much as when a photographic subject moves during the snap -- patients are usually asked to hold their breath during the exposure.

The final product is stored on a piece of film, the radiograph. The radiographs are read by the radiologist, a physician specially trained to interpret the images. The x-ray diagnosis is transcribed into a written report and sent to the requesting physician.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.