Safety Corner, v1.1

Explaining Radiation Risk

In this installment of Safety Corner we discuss the risks associated with medical procedures. With  the heightened awareness of radiation from medical procedures more and more patients are asking,

“How much radiation am I getting”? Or, “What do all of these numbers mean?”

As part of everyday living, everyone is exposed to a small amount of what we refer to as “background radiation”. This background radiation comes from space and naturally-occurring radioactive minerals all around us that that cannot be avoided. For example, the average person in the Charlottesville area receives an estimated 8 µSv (micro Sieverts) per day without undergoing any medical imaging.

To put this value into perspective, for a single view chest X-ray you could receive an estimated two and one half times this amount of background radiation. For the actual risk associated with that X-ray, that is,

“If I have a chest X-ray, how much could I increase my risk of getting cancer?”

According to the American Association of Physicists in Medicine (AAPM), risks from medical imaging with radiation doses below 50 mSv (milli Sieverts) for a single exposure over a short time period may be too low to be detectable and may be nonexistent. Again for perspective, this 50 mSv value is 2500 times more radiation than the Single View Chest X-ray described above. Of course many procedures do have more radiation associated with them. However, discussion of risks related to radiation dose from medical imaging procedures should also be accompanied by acknowledgement of the benefits of the procedures. So yes, many times a CT exam or another similar procedure may carry more risk, but the tremendous benefit of these exams are often lifesaving and should not be overlooked.