Yale New Haven Health has joined a number of hospitals across the country that are ending their practice of using lead aprons during X-ray exams.
The health system has so far stopped using the aprons at Yale New Haven Hospital and is ending the practice completely at Bridgeport Hospital. It plans to do the same at other Yale New Haven Health providers, including Greenwich Hospital, reported LMTonline
"For at least a decade, the medical physics community and radiology community have realized that the pelvic shielding on patients was providing little, if any, benefit in helping decrease radiation dose to the gonads (reproductive organs)," Dr. Jay Pahade, radiology medical director for quality and safety at Yale New Haven Health, told HCB News. "Dose reduction technology has also played a role in changing this practice, as overall radiation doses for X-rays have fallen significantly over the last 50 years. In addition, use of newer technology like automated exposure control (which is designed to keep image quality consistent by automatically increasing or decreasing radiation dose for patients of different sizes) can function poorly if the lead is accidentally placed inside the field of view of the X-ray."
Used primarily to protect ovaries and testes from radiation, radiologists and doctors have questioned for a long time if these shields actually do any good, since the amount of radiation in modern X-rays is low. Radiologyinfo.org says that a chest X-ray delivers as much as 10 days of background exposure, a mammogram is equivalent to seven weeks and a scan of a hand or foot is about three hours.
Lead shields became standard in the 1950s when radiation levels for X-rays were about 10 times higher than they are today. The concern was that radiation could cause genetic defects in ova and sperm, and there was also a small risk of radiation causing cancer in internal organs. Research shows lead shielding does little to protect these areas from radiation that might cause genetic defects or cancer, and that it may even increase the amount of radiation a person is exposed to.
For example, if the lead shield is detected by the machinery, “it will actually be seen … as if it is a large person” and increase the amount of radiation, Adel Mustafa, Ph.D., chief physicist at Yale New Haven Hospital department of radiology and biomedical imaging, told LMTonline.
Shields can also block parts from the scan that must be imaged, causing the patient to have to undergo the exam a second time and be exposed to more radiation.
The continued use of shields stems from a standard that radiologists follow called ALARA, which stands for as low as reasonably achievable. The American Association of Physicists in Medicine recommended in April 2019 that lead shields be discontinued. Yale New Haven planned to change its practice in July but made the switch instead in March due to the COVID-19 pandemic, as staff found it took additional time to clean aprons and there was an increased risk of infection from COVID-19.
Yale New Haven Hospital believes the practice will eventually become obsolete, as it doesn't have much scientific merit to continue, but that it will take time for that to happen.
"Big changes in medical practice take time to spread and implement, especially ones that don't necessarily harm patients," Mustafa, told HCB News. "Lead shielding doesn't present much risk of harm to a patient, but it certainly doesn't provide much value either, based on what we now know about radiation biology and internal/external scatter radiation, and what the external lead shield actually does for reducing dose to the gonads. In addition, many states have some regulatory guidelines calling for shields to be used on patients during their X-ray exams, so that language needs to be updated on a state-to-state basis."