Are You Aware? Ionizing Radiation Risks in Medical Imaging: What Doctors Need to Know
"A New Survey Reveals Gaps in Clinician Understanding of Radiation Exposure from CT Scans and X-Rays."
Medical imaging, particularly computed tomography (CT) scans and X-rays, is a cornerstone of modern healthcare, providing invaluable insights for diagnosis and treatment. However, these technologies utilize ionizing radiation, which carries inherent risks, including an increased lifetime risk of cancer. Ensuring that healthcare professionals, especially doctors, are well-informed about these risks is paramount for patient safety and responsible utilization of imaging resources.
A recent study delved into the knowledge and awareness of doctors regarding the risks associated with ionizing radiation exposure from imaging investigations. The research highlights a critical need for improved education and awareness among clinicians to minimize unnecessary radiation exposure and promote informed decision-making.
This article will explore the findings of this survey, shedding light on the gaps in doctors' understanding of radiation risks and discussing the implications for patient care. We'll examine the specific areas where knowledge is lacking and discuss potential strategies for enhancing education and promoting safer imaging practices.
Risk and Uncertainty
The ICRP says effective dose can serve as an approximate indicator of possible risk, while noting uncertainty in projecting risk at low doses or low dose rates. It also says lifetime cancer risks vary with age at exposure, sex, and population group. The CDC notes that imaging uses low amounts of ionizing radiation: cells can normally repair DNA damage at these levels, though short- and long-term risks are possible.
Balancing Benefits and Risks
The CDC advises patients to discuss the specific risks and benefits of a recommended imaging test with their healthcare provider, including ways to limit radiation exposure. A National Academies chapter addresses how ionizing-radiation risks are estimated and how they are considered in regulatory authority. A 2025 overview also discusses technological advances that have mitigated dose exposure and best practices for patient and staff safety.
The Knowledge Gap: What Doctors Don't Know About Radiation Risks
The survey, conducted at a Royal Derby Hospital in England, involved an online questionnaire completed by doctors regarding their education and knowledge of the risks associated with ionizing radiation. Out of 647 doctors contacted, 170 (26%) responded, revealing some concerning gaps in understanding:
- CT Scans and X-Rays: Almost all respondents correctly identified CT scans (98%) and chest X-rays (97%) as sources of ionizing radiation.
- Isotope Bone Scans and PET Scans: A substantial proportion also recognized isotope bone scans (84%) and positron emission tomography (PET) scans (81%) as involving radiation.
- MRI and Ultrasound: Worryingly, very few identified magnetic resonance imaging (MRI) scans (8%) and ultrasound scans (4%) as utilizing radiation, despite MRI using non-ionizing radiation and ultrasound using sound waves, indicating a basic misunderstanding of imaging modalities.
- Lifetime Cancer Risk: When asked about the lifetime cancer risk associated with a chest, abdomen, and pelvis CT scan for a 20-year-old female, only 22% identified the optimal response (one in 300). A significant 27% underestimated the risk as one in 30,000 or negligible.
Evolving Evidence and Practice
A September 3, 2025 manuscript, “Ionizing Radiation Exposure: What are the Risks Today?”, reviews risks from medical imaging, technological advances that have mitigated dose exposure, and best practices for patient and staff safety. The PubMed record highlights the challenge for radiology of balancing medical imaging’s diagnostic benefits against potential risks from ionizing radiation. Together, these sources frame risk management alongside the continued diagnostic role of imaging.
Limits of Risk Estimates
Radiation-induced latency periods can last many decades, while pediatric CT studies with follow-up of about 10 years provide only a snapshot and cannot directly estimate lifetime cancer risks. Human exposure data are extremely limited, so estimates draw on higher-dose exposures above 100 mGy and animal and cellular studies that mostly used doses on the order of Gy, rather than the tens of mGy used in medical imaging. CT risk estimates also face limitations such as missing patient-specific dose estimates and medical records, increasing uncertainty.
Diagnostic Value and Radiation Risk
Medical imaging involves balancing the benefits of detailed internal imaging and diagnostic capability against potential long-term health risks from radiation exposure. The historical trajectory of imaging reflects an ongoing effort to manage that balance. Early radiological practices lacked a comprehensive understanding of radiation’s biological effects, which led to excessive exposures.
The Path Forward: Improving Awareness and Protecting Patients
The survey underscores the urgent need for comprehensive and ongoing education on the risks of ionizing radiation for all healthcare professionals. Addressing the identified knowledge gaps is crucial for promoting responsible imaging practices and ensuring patient safety.
Keeping Protection Current
As medical imaging continues to evolve, radiation-protection experts gathered at the IAEA in 2024 to discuss how to keep patients safe in a changing medical landscape. The IAEA reports that a new imaging technology using ionizing radiation enters the market every five years. This pace makes patient protection an ongoing consideration as imaging technologies change.
Several strategies can be implemented to improve awareness and education:
<ul> <li><b>Mandatory Education:</b> Hospital doctors should receive regular mandatory education on the long-term risks of patient exposure to CT scans and other imaging procedures involving ionizing radiation.</li> <li><b>Alternative Strategies:</b> Promote the consideration of alternative diagnostic strategies that avoid exposure to ionizing radiation when possible, such as ultrasound or MRI (when appropriate).</li> <li><b>Risk Communication:</b> Enhance communication with patients about the potential risks and benefits of imaging procedures involving radiation, empowering them to make informed decisions about their healthcare.</li> </ul> By implementing these strategies, healthcare institutions can foster a culture of radiation safety and minimize unnecessary exposure, ultimately protecting patients and promoting responsible utilization of medical imaging resources.