What are X-rays?
- The use of X-rays allows physicians to look inside the body to diagnosis an injury or illness. When done for appropriate situations, X-rays are safe and beneficial. It is important that X-rays are not misused or overused because over a lifetime, a person may be exposed to a fairly large amount of cumulative radiation, and it is important than the benefit of each X-ray test be considered before it is done.
- Radiologic technologists are trained to use the least amount of radiation possible to produce an image that will help with diagnosis. The technologist or the radiologist (the physician who supervises the testing and then interprets the X-ray images) is often able to tell the patient how much radiation is being used.
- If you ask, and are told a dose of radiation, you may not understand what a dose of 1 millisievert (mSv) might mean. But if this effective dose is converted into the amount of time it would take you to accumulate the same effective dose from background radiation, you could make a comparison. For example, the average background rate of radiation you are exposed to from the environment just by living in the United States is about 3 mSv per year. So a mammogram with a dosage of 1 mSv would translate into the amount of radiation you would get by just living in the U.S. for about four months.
- This method of explaining radiation is called Background Equivalent Radiation Time or BERT. The idea is to convert the effective dose from the exposure to the time in days, weeks, months, or years it would take to obtain the same effective dose from background radiation. This method has also been recommended by the United States National Council for Radiation Protection and Measurement (NCRP).
- However, radiation doses may accumulate quickly, depending upon the situation. A trauma victim who is critically injured may be exposed to 30 mSv during treatment. To put this in perspective, a Hiroshima survivor may have been exposed to 50-150 mSv of radiation.
Medically Reviewed by a Doctor on 6/23/2017
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