Interventional Radiology: What can I do? - Medical Physicists
"Child-size” the radiation delivered to pediatric patients
Children are more sensitive to radiation and have a lifetime to manifest the effects of exposure. Currently, medical imaging (with interventional radiology the third largest dose contributor in medicine following CT and nuclear medicine) may exceed background radiation as the single largest source of radiation for the American population (NCRP, 2009). It is also noteworthy that in the last 26 years the per capita dose from medicine increased by 570%. A 2005 report from the Biological Effects of Ionizing Radiation (BEIR) Committee of the National Academy of Sciences concluded that “the risk of cancer proceeds in a linear fashion at lower doses without a threshold and that clinical CT doses result in a potential small increased risk to humans.”
That being noted, interventional radiology (IR) procedures are critically important tools for diagnosing and treating illnesses in children, and improving outcomes. Still, it is both logical and prudent to implement policies and techniques for reducing radiation dose when performing IR procedures on children. Every member of the healthcare team should ensure that whenever an IR procedure is prescribed for a child, it is completed only after careful consideration on an individual basis.
Medical physicists are responsible for maintaining imaging equipment in proper working order, maintaining or improving image quality, carefully managing patient dose by advising healthcare providers on appropriate techniques, providing training/education to employees and consulting with parents and providers on radiation issues. As the experts on radiation issues, they can provide invaluable guidance on how to “child-size” everyday procedures for radiologists and radiologic technologists who may be more accustomed to practicing in an adult environment. The knowledge and experience provided by medical physicists is vital to ensuring that young patients are treated using radiation as low as reasonably achievable (ALARA). It is important to recognize that pediatric interventional radiology is a discipline in itself. However, basic medical physics principles in adult radiology equally apply to pediatric radiology.
Interventional radiology (IR) has seen many advances in recent past such as HDR fluoroscopy, incorporation of flat-panel detector, and 3-D imaging capability with cone beam CT (CBCT). As a result, dose characterization of modern IR machines has become very complex. IR presents not only skin burn issues (non-stochastic effect) but also stochastic risks to organs that are irradiated. At present, no definitive dose indices exist that can relate to organ doses and effective dose. Although IR dosimetry lags behind the advances of imaging equipment, new technology such as MOSFET detectors may enable measurement of organ doses in near real-time. Numerous dose indices exist in IR but none serves as a standard dose index like CTDI in computed tomography. Medical physicists should also be cognizant of the importance of skin doses (JC reporting mandate above 15 Gy) and specific organ doses as the latter may become important in cancer risk estimation. Medical physicists should establish a networking relationship with other medical physicists as accurate dose assessment tools may not be immediately available in your institution.
The knowledge and experience provided by medical physicists is vital to ensuring that young patients are imaged using radiation as low as reasonably achievable (ALARA). Towards this goal, this website provides simple educational resources to inform radiology practices on what can be done now to improve radiation protection for children.
By logging in, you have already demonstrated your commitment to this important initiative.
Here are 5 simple steps to improve patient care in your everyday practice:
- Increase awareness for the need to decrease radiation dose to children during IR procedures.
- Be committed to make a change in your center's daily practice by working as a team with its radiologists, technologists, equipment engineers, manufacturers, administration, referring doctors and parents to decrease the radiation dose. Sign the pledge! Click on the link on the home page to join the image gently™ campaign today.
- Review your imaging center’s IR procedures and equipment and then discuss the simple dose reduction steps on this website with your center’s radiologists and technologists to “down-size” the protocols for kids as appropriate.
- Establish training program on radiation safety, equipment QA, patient dose monitoring and follow-up, and dosimetry oversight and consultation. Participate in institutional oversight activities including radiation safety and regulatory committees.
- Network with other medical physicists working with pediatric institutions for mutual support and consultation. Join the discussion group at http://www.safety.duke.edu/RadSafety/drdl/peds_ir_network.asp. Visit the American Association of Physicists in Medicine at http://www.aapm.org/ and the Health Physics Society at http://hps.org/publicinformation/asktheexperts.cfm.
Your patients and their families will thank you