In response to member requests for formal guidance for radiologists, the CAR issued a position statement on the discontinuation of gonadal and fetal shielding for patients undergoing diagnostic X-ray examination. Routine shielding of patients remains common practice despite current scientific evidence that the practice provides negligible or no benefit and carries a substantial risk of increasing the patient’s radiation dose and compromising the diagnostic efficacy of imaging.
The new position statement builds on prior CAR efforts to advocate for the discontinuation of gonadal and fetal shielding. In October 2019, the CAR endorsed the American Association of Physicists in Medicine (AAPM) position statement recommending the discontinued routine use of gonad and fetal shielding in diagnostic X-ray exams. The AAPM statement was endorsed by multiple other organizations representing key stakeholders in medical imaging, including the American College of Radiology (ACR) and Canadian Organization of Medical Physicists (COMP). The CAR also supported the publication of an invited editorial in the CARJ on fetal and gonadal shielding in February 2021.
Gonadal and fetal shielding have been part of routine practice for over 40 years, with many jurisdictions requiring routine use via program accreditation or regulation. In Canada, federal-level guidance on shielding is provided by Health Canada Safety Code 35, last updated in 2008 (citing now-defunct CAR standards from 2005). Health Canada advises the use of gonadal shields if (1) the gonads lie within or are in close proximity to the X-ray beam; (2) the patient is of reproductive age; and (3) clinical objectives will not be compromised.
An extensive body of peer-reviewed scientific literature and expert consensus has shown that there is negligible, or no, benefit to patient’s health from gonadal and fetal shielding when imaging is conducted using current equipment. In most circumstances, the use of gonadal shields does not reduce the patient’s risk of radiation exposure and may degrade the diagnostic efficacy of the images.
Regulatory and accreditation standards must also be updated to reflect current evidence. The CAR is actively engaged with Health Canada, advocating for an update of Safety Code 35. The radiology community at large should engage with other medical imaging professions and appropriate government and accreditation agencies to press for the necessary regulatory changes to bring shielding practices in line with the evidence. Until regulatory frameworks and standards are updated, radiologists, technologists, and medical physicists are bound to adhere to shielding requirements.
Summary of Recommendations
Based on current scientific evidence the Canadian Association of Radiologists (CAR) recommends:
- Discontinuing the routine use of gonadal and fetal shielding for patients undergoing abdominal or pelvic X-ray diagnostic imaging.
- That radiologists work with their medical imaging team colleagues to advocate for the necessary changes to local institutional policies and procedures to ensure those policies are reflective of current evidence regarding shielding.
- That if existing regulatory and/or accreditation standards require shielding, that those requirements be adhered to until standards are changed.
- That during the period of transition to new policies and procedures, if a patient, parent, or guardian requests the use of shielding, that it be provided.