03/18/2010 05:12 am ET Updated Nov 17, 2011

Another Look at Radiation

I have previously discussed general safety issues about ionizing radiation as it applies to imaging studies (e.g., CT, X-ray, etc.), but thought I would get a little more specific.

It is important to remember that radiation is all around us, naturally present in our environment. The actual dosage of background radiation varies with where one lives. The radiation we receive annually is called "background radiation" and is approximately 200-300 millirems (millirems (mrem) is used to measure radiation) per year or 2-3 mSv (another measurement term) effective dose. The "effective" dose is a calculation, which estimates what dose, if given to the entire body, might produce approximately the same amount of risk as would the real dose actually received by the irradiated body part.

How does this translate with imaging studies? A two view chest x-ray for instance, is approximately 6-8 mrem or 0.06-0.08 mSv. Basically, if there is medical indication for the examination, the fear of radiation should not be the reason to avoid getting the examination. Exposure to ionizing radiation during a medical examination can be limited by lead shielding, tube collimation and using the lowest dose necessary to obtain a diagnostic image. Limiting the radiation dose requires that the radiology technologist and the physician supervising the image acquisition are appropriately trained and experienced. For the technologist, a registered radiology technologist receives an RT and is accredited by the American Registry of Radiologic Technologists and also requires State Licensure. For the Radiologist, the American Board of Radiology validates the four years post medical school residency in Radiology which encompasses learning the physics associated with the hazards of ionizing radiation and how to maximize patient safety in addition to being trained in how to optimize image acquisition and image interpretation. This, of course, goes back to the message I have been communicating in many of my prior posts regarding the importance of working with trained and experienced radiologists and radiology technologists for all medical imaging needs.

In a recent post I commented on imaging studies and the effect of ionizing radiation on children and provided some thoughts on what to do prior to having an imaging study. Many of the same principles that were emphasized for children should be considered for adults as well. Remember X-rays and CT scans help save lives and initiate early and appropriate intervention, but patient safety is of the utmost importance. Your imaging provider is most likely taking the necessary steps to ensure your safety, but it never hurts to inquire.