Is it time to end patient shielding in radiology?

Though it has been in place for decades, the practice of patient shielding in radiology should be abandoned, according to a new analysis published in the American Journal of Roentgenology.

“The assumption is that shielding improves patient safety,” wrote authors Rebecca M. Marsh, PhD, and Michael Silosky, University of Colorado School of Medicine in Aurora. “This belief is often regarded as fact, with little consideration given to its veracity. However, a review of the history of patient shielding and the current role of patient shielding in radiology provides evidence that the associated risks are substantial, whereas the benefits are negligible or nonexistent.”

Patient shielding first began in 1976, the authors explained, due to concerns about the hereditary effects of radiation exposure. To this day, however, there have been no observed hereditary effects from radiation in any human. Marsh and Silosky also added that much less radiation is used during imaging exams today than when patient shielding first became common practice, showing how much the industry has evolved since then.

The two authors noted that it is also important to think about how much protection is really being provided to the patient.

“For anatomy outside the imaging field of view (FOV), radiation exposure results almost entirely from internal scatter generated within a patient,” they wrote. “Because contact shielding cannot protect against internal scatter, shielding anatomy outside the imaging FOV provides negligible protection to the patient. This holds true for all examinations, including those of pediatric and pregnant patients.”

In instances when patient shielding may make an actual difference on the radiation dose, Marsh and Silosky explained, there's a chance that it could lead to the “diagnostic efficacy of the examination” being jeopardized. On a similar note, there are times when shielding can lead to an increase in repeat rates, specifically during pelvic x-rays.

So how could a department go about changing the practice of patient shielding? Marsh and Silosky realize it would be viewed as a “significant departure” and may be hard to explain to patients concerned about radiation exposure. The two authors suggested that those concerns would need to be discussed with the patient before the exam, possibly by the technologist during that traditional introduction period.

“This gives the patient the opportunity to ask questions and express any concerns he or she may have,” they wrote. “In addition, information in the form of posters or brochures can provide information to patients before an appointment, either online or in a waiting room. The concerns of many patients may be alleviated if the patients know that someone is paying attention to their safety and that the lack of shielding is intentional rather than negligent.”

Another key point is that technologists will still be able to provide shielding when it does make sense. If a patient is especially nervous, for example, than there is the possibility that it is worth the “psychologic benefit” of providing shielding during the exam.

“Although change is difficult, it is incumbent on radiologic technologists, medical physicists, and radiologists to finally step up as reasonable voices on the subject,” Marsh and Silosky concluded. “ Until then, training programs, health care facilities, and accreditation and regulatory bodies will continue to encourage and engage in a legacy practice that presents substantial risk but negligible (or no) benefit to patient health.”