AJR March 2017
Jay R. Parikh
Department of Radiology
University of Texas MD Anderson Cancer Center
A. Kyle Jones
Department of Imaging Physics
University of Texas MD Anderson Cancer Center
Potential Radiation-Related Effects on Radiologists
While the risk of injury associated with occupational exposure to ionizing radiation is low for radiologists, a plethora of data regarding radiation-related effects exists. This article weeds though the information in an effort to provide an educational update and identify opportunities for improved radiation protection for practicing radiologists.
1. How do you balance the risk of radiation against the loss of tactile sensitivity and possible orthopedic injury associated with using safety gear?
Be practical and use your knowledge of radiation physics. Radiation attenuation is exponential, and therefore, increases in shielding thickness have diminishing returns. A 0.35-mm lead (Pb) garment will attenuate about 97.5% of scattered radiation from an 80-kVp beam, while a 0.5-mm Pb garment will attenuate about 99.2%. Always choose a garment that fits well, and consider using a 0.35-mm garment instead of a 0.5-mm garment. Or shift the weight to the ceiling using ceiling-mounted personal protection. Always wear your occupational dosimeter correctly, and consider a two-badge method if you are really interested in seeing how your choice of protective garment is working. The majority of the scientific literature does not support the use of protective gloves, and the extremity dose limit is much higher than the whole-body dose limit.
2. Other than the use of protective gear, are there additional strategies for reducing radiation risk?
Time, distance, and shielding. It sounds trite but it’s true. Move half a meter farther from the patient before releasing x-rays during fluoroscopy. Use remote fluoroscopy when possible, and go into the control room when using acquisition imaging or digital subtraction angiography (DSA). Use good practice during fluoroscopy, which includes setting up a good geometry and collimating tightly to the area of interest.
3. Are interventional radiologists at a higher risk of radiation exposure than other radiologists?
Yes. The two most exposed groups in a radiology department are interventional radiologists and PET technologists. Radiologists who perform fluoroscopic procedures such as lumbar punctures and cystourethrograms are exposed to more radiation than those who do not, but the total exposure is very small compared to that of interventional radiologists. Radiologists who do not perform fluoroscopic procedures are generally exposed to no more radiation than the general public.
4. What type of radiation safety training would you recommend for radiologists?
Although radiologists do receive education in radiation physics and safety during their training, the quality of that education varies, and medical imaging technology evolves rapidly. Our understanding of radiation risks and effects is also evolving. It is prudent to devote at least a few continuing medical education (CME) courses to refresher training on radiation safety every few years, and there are several high-quality CME educational programs that can meet this need.
5. If radiologists and other medical workers follow safety procedures, would you say that their risk of exposure is minimal?
Yes. Specifically, our systematic review shows that the balance of the literature supports the hypothesis that radiation-induced skin cancers, breast cancer, and leukemias in radiologists working before 1950 are linked to high occupational doses. There is no credible evidence of increased risk of cancer among radiologists who have been practicing the past 30 or 40 years. This is likely due to increased radiologist awareness and education, with careful attention to good radiation protection habits.
6. Where can medical radiation workers find the most updated information on practices and procedures associated with reducing exposure?
Practice standards from the American College of Radiology (ACR) and practice guidelines from the Society of Interventional Radiology (SIR) are two great sources. The American Association of Physicists in Medicine (AAPM) also has numerous resources, including task group reports and the Educator’s Resource Guide at http://www.aapm.org/education/ERG/. Medical radiation workers should also be familiar with standards from the National Council on Radiation Protection and Measurements (NCRP).
7. What is the most important new information revealed in this study?
The breadth of literature regarding radiation injury and safety spans multiple disciplines and multiple journals and is rapidly evolving. Formal educational updates with CME courses every few years, careful attention to good radiation protection habits, and continued emphasis of the as low as reasonably achievable (ALARA) principle are recommended for all radiologists.
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