The average individual might be quite shocked to find out that exposure to low-level radiation is as common as the air we breathe. Everyday sources of radiation include the sunlight that allows us to visibly function, the natural minerals beneath our feet, the cosmic radiation that enters our atmosphere, radon in the air we breathe, and, of course, the medical imaging that allows us to diagnose disease and injury. The National Council on Radiation Protection and Measurement (NCRP) estimates that the average individual is exposed to 3.6 milliSieverts (mSv) of radiation per year, an insignificant amount relative to the 4,000 mSv fatal dose of radiation predicted by the U.S. Environmental Protection Agency (EPA). Looking at these numbers it seems that we shouldn’t be concerned about our radiation exposure— however, the EPA also reports that even doses of 5-10 mSv may cause changes in blood chemistry, 50 mSv may cause nausea, and 100 mSv could lead to hemorrhaging. To put this into perspective, it is estimated that a single CT scan, depending on the individual patient and location of the scan, can amount to up to 20 mSv, suggesting that individuals who undergo multiple imaging procedures as a consequence of injury or illness may be at risk for the physiological impacts of that exposure. Given the ever-increasing amount of medical radiation imaging within the span of the last two decades, should we be concerned about the impact of radiation on our everyday lives?
Given the ever-increasing amount of medical radiation imaging within the span of the last two decades, should we be concerned about the impact of radiation on our everyday lives?
The use of ionizing radiation, energy emission in the forms of electromagnetic waves, is arguably one of the greatest technological medical advancements of the 20th century. From the very first X-Ray scan by German physicist Wilhelm Röntgen of his wife’s left hand to the invention of the Computed Tomography (CT) scan in 1972 and the invention of Magnetic Resonance Imaging (MRI) in 1977, medical ionizing radiation imaging has taken great leaps and bounds in the Twentieth century and continues to increase in complexity and in its prevalence in medicine. The NCRP reports that the use of medical imaging, most significantly the CT scan, has steadily increased since its discovery. Echoing this trend, Dr. Rebecca Smith-Bindman et al. published an article in JAMA citing a 7.8% annual increase in the number of scans carried out from 1996-2010 alone. This effect has also been observed in positron emission tomography and MRI. And not only are imaging scans becoming more frequent— Smith-Bindman states that the average effective dose of radiation per scan increased from 4.8 to 7.8 mSv over that same time period.
Smith-Bindman argues that while CT scans are a valuable diagnostic tool, “unnecessary use may lead to a small but real increase in a patient’s risk of cancer.”
What are the implications of this increase? Smith-Bindman argues that while CT scans are a valuable diagnostic tool, “unnecessary use may lead to a small but real increase in a patient’s risk of cancer.” An opposing view reflects the idea of hormesis, the idea that low levels of exposure to somewhat toxic environmental factors, including ionizing radiation, may actually induce beneficial results. David Warmflash states in an article published by Discover Medicine that “…there may exist doses, above the normal background radiation and below the threshold for harmful effects, that can actually provide health benefits.” The question is, where does this threshold exist? In one study cited by Warmflash, the effect of low dose radiation (LDR) in diabetes was assessed. Preliminary research with diabetic rats resulted in reduced kidney failure, faster wound healing, and other health improvements. However, further research on LDR treatment for canines showed increased DNA repair and cell proliferation but ultimately led to a greater risk of leukemia. These results suggest that regardless of whether or not there is a “healthy” dose of radiation, there is a fine line between that dose and one which increases an individual’s risk of cancer. Dr. Eugene C. Lin of the U.S. National Library of Medicine argues that while low-dose radiography (<10 mSv) has not been correlated with increased cancer risk, “this does not mean that this risk is not present, as even large epidemiological studies would not have the statistical power to detect increased risk, if present, at a low radiation dose.”
There are many hypothetical causes for the increase in imaging use in recent decades. Explanations include increased accessibility of medical care, technological advancements that have expanded the capabilities of imaging techniques, and other confounding factors. However, one proposed factor is the practice of “defensive medicine,” or the excessive use of diagnostic techniques to prevent lawsuits. In the Journal Sentinel, Cary Spivak reports that the number of medical adverse action reports filed increased from 4454 to 6105 cases in the last decade. Doctors are faced with greater accountability as a result of this, and must naturally be more cautious in their diagnoses. It is possible that physicians may feel pressured to perform more diagnostic testing than is required in order to cover their bases, and medical imaging is likely a tool that is often used to do so. Drs. Jesse M. Pines and Zachary F. Meisel describe this phenomenon in the New York Times, claiming that today’s doctors rely on radiology scans as a “crutch” for their own incompetence or inability to assess injury and disease. Pines and Meisal even go so far as to state that“testing has become more of a reflex than a higher-level decision.” The article captures the need for physicians today to be wise in their decision to administer an imaging scan and have more faith in their ability to diagnose patients.
So should one forego entirely the brilliant innovation and aid of medical radiation technology for fear of the risk of radiation? Certainly not.
So should one forego entirely the brilliant innovation and aid of medical radiation technology for fear of the risk of radiation? Certainly not. It is irrefutable that the presence of ionizing radiation imaging within the medical field has saved thousands upon millions of lives and offers significant benefits as a diagnostic tool when appropriate. I merely suggest that the medical community should strive to limit radiation exposure to cases where it is truly necessary. In his article cited above, Dr. Lin lays out a three-step plan to reduce the amount of medical imaging scans in America that could aid in this goal: “first, one can decide not to perform the study at all. …Second, an alternative study that does not use ionizing radiation can be selected. Third, [a lower dose of] radiation can be used” if it is still sufficient to produce clear results. Adding a fourth step, individual education and knowledge of medical imaging could be the key to lessening the excessive use of medical radiation in America and worldwide. One shouldn’t yell at their physician and accuse him or her of incompetence every time a scan is issued. Instead, patients should talk with their doctors and understand the procedure being suggested and their individual need for it as well as any risks associated with it. Ultimately, as in many issues in healthcare, an effective partnership between patients and physicians could resolve these concerns entirely.
Lin, Eugene C. “Radiation Risk From Medical Imaging.” Mayo Clinic Proceedings 85.12 (2010): 1142–1146. PMC. Web. 09 Aug. 2015.
Pines, Dr. Jesse M., and Dr. Zachary F. Meisel. “Why Doctors Order Too Many Tests (It’s Not Just to Avoid Lawsuits).” Time. N.p., 25 Feb. 2011. Web. 11 Aug. 2015. <http://content.time.com/time/health/article/0,8599,2053354,00.html>.
“Radiation and Health; How does radiation cause health effects?.” United States Environmental Protection Agency. N.p., n.d. Web. 29 June 2015. <http://www.epa.gov/radiation/understand/health_effects.html>.
“Radiation Dose in X-Ray and CT Scans.” RadiologyInfo.org. N.p., 2015. Web. 9 Aug. 2015. <http://www.radiologyinfo.org/en/info.cfm?pg=safety-xray>.
Smith-Bindman, Rebecca, et al. “Use of diagnostic imaging studies and associated radiation exposure for patients enrolled in large integrated health care systems, 1996-2010.” Jama 307.22 (2012): 2400-2409. <http://jama.jamanetwork.com/article.aspx?articleid=1182858>.
Spivak, Cary. “Medical malpractice lawsuits plummet in Wisconsin.” Journal Sentinel. N.p., 28 June 2014. Web. 9 Aug. 2015. <http://www.jsonline.com/watchdog/watchdogreports/medical-malpractice-lawsuits-plummet-in-wisconsin-b99290329z1-264436841.html>.
“Update of Report No. 93.” National Council on Radiation Protection & Measurement. N.p., 2015. Web. 9 Aug. 2015. <http://www.ncrponline.org/Current_Prog/93_Update.html>.
Warmflash, David. “Could Small Amounts of Radiation Be Good For You? It’s Complicated.” Discover: Science for The Curious. N.p., 6 Apr. 2015. Web. 9 Aug. 2015.<http://blogs.discovermagazine.com/crux/2015/04/06/small-radiation/#.Vcn7op1Vikp>.
Waters, Hannah. “The First X-Ray, 1895.” The Scientist: Exploring Life, Inspiring Innovation. N.p., 1 July 2011. Web. 9 Aug. 2015. <http://www.the-scientist.com/?articles.view/articleNo/30693/title/The-First-X-ray–1895/>.