On November 28, 2017, the US Food and Drug Administration (FDA) released new guidance on pediatric x-ray imaging, including Pediatric Information for X-ray Imaging Device Premarket Notifications. Medscape spoke to Vasum Peiris, MD, MPH; Laurel Burk, PhD; and Gail M. Rodriguez, PhD, from the FDA about this guidance and its importance to x-ray equipment manufacturers and healthcare providers in helping them to continually improve the safe imaging of children.
The Right Dose for the Right Patient at the Right Time
Medscape: We'd like to start with you explaining the particular concerns with children and imaging. Obviously, there are issues besides their smaller size. Would you elaborate on that?
Vasum Peiris, MD, MPH
Dr Peiris: You're absolutely right about the issue of the smaller size. At the FDA, when we think about pediatric devices, we include newborns all the way through persons aged 21 years. That's a vast spectrum of anatomy and physiology.
With respect to imaging, specifically imaging using ionizing radiation, the body size is probably more important than age. We recognize that children, especially smaller children, may receive scans using adult-sized imaging protocols. We should ensure that children and adults with smaller body surface areas and body sizes are exposed to the appropriate amount of radiation when an imaging exam is done—and that's really what we're emphasizing here.
Laurel Burk, PhD
Dr Burk: We emphasize the right dose for the right size patient at the right time.
Medscape: Are there also issues with an increased sensitivity of children to radiation, or concern about a longer lifetime risk?
Dr Peiris: It is a bit of a complex topic, but simply put, we do believe that children might be a little more radiosensitive to ionizing radiation. Different organs are probably variably sensitive. In addition, children may, over a lifetime, have exposure to multiple medical examinations and potentially have x-ray imaging as part of the medical management. Therefore, they may have a predilection for more ionizing radiation exposures, and so it's important to ensure that—as Dr Burk said so well—we use the right dose for the right patient at the right time.
Medscape: Is there an additional concern about a possible increased risk for cancer due to exposure to radiation?
Dr Peiris: Yes, there is a concern that exposure to excessive amounts of radiation may lead to an increase in cancer risk—but the reality is that additional cancer risk is relatively small. The key point here is that when a clinician orders an x-ray exam, the benefits of that exam greatly outweigh the risks for potential development of cancer.
We're not suggesting that radiation exposure from diagnostic imaging is going to significantly increase the risk for cancer. We don't want parents or children to be alarmed in any way. Most physicians are cognizant of the need to use pediatric protocols, especially with diagnostic imaging and radiation exposure. They try to make the right determinations about doing any type of study, including diagnostic imaging.
Dr Burk: Whenever there is any possibility of risk, even if it is quite small, we want to make sure that we minimize that to the extent possible. That's what we're hoping to encourage with this guidance. We also hope that industry will think specifically about pediatric patients when they're designing their equipment, empowering the clinician to make sure that the imaging exam is appropriately sized for that specific pediatric patient population.
Dr Peiris: In addition to supporting manufacturers, we want to help clinicians understand the features of the devices and also ensure that information about dose management techniques is easily accessible and easy to use.
Dr Burk: We hope that the information that manufacturers will provide as a result of following this guidance will empower clinicians and give them information so that whether the clinicians are working at a community hospital or a children's hospital, those exams will be appropriately tailored to the age and size of the pediatric patient. So it doesn't matter where a child is receiving an exam, it will be at the right dose, at the right time, and for the right-sized patient.
Dr Peiris: We realize that pediatric expertise is variable across the country. Certain hospitals may not be as familiar with pediatric imaging protocols; some clinicians and technicians may not be aware of how to make the dose appropriate for children. Our goal is to make it as easy and simple as possible to ensure that children are exposed to the lowest dose needed to obtain the necessary information for their care.
Medscape: If a small community hospital is using a general x-ray machine, can that equipment always be dosed correctly for children and small adults? Or is part of the issue that some are using equipment that cannot be dosed correctly, and that needs to change as well?
Dr Peiris: All of the equipment that has been approved by the FDA and currently in general use should be able to be used appropriately for children. That capability exists, and we want to ensure that the information on how to do that is available and easily accessible to the technologists and the clinicians.
Dr Burk: It is important to make it easy. If a clinician can make sure that he or she has the right protocols with the push of a button or with easily accessible instructions, that will help empower the clinician to use the correct protocols and techniques.
Medscape: What do you believe the key take-away points are from these recommendations for healthcare professionals?
Dr Peiris: I trust that most clinicians are aware of the potential risks with radiation exposure. They have to consider several factors to make the appropriate decisions about when and what type of an exam is necessary for any patient, including children, and we want to help support them in making these types of decisions.
We want to help physicians think about whether there may be another type of imaging modality, such as ultrasound or MRI, that doesn't expose the patient to ionizing radiation. Sometimes they might be able to use those alternate options instead of an x-ray–type exam.
Of course, we recognize that each of those modalities has benefits that the others don't. For instance, getting an MRI might take a lot longer than getting an x-ray, and if a clinician is looking for a fracture, an x-ray is the quickest and standard method. A clinician is not going to do an MRI when a child with a broken bone is in significant pain; we want to take care of that child as efficiently as possible. Considering these and many other factors, each physician has to make a decision about what study is best for their patient at the time of the evaluation. We'd like to ensure that information to support those decisions is readily available.
Medscape: In daily clinical practice, would you expect any pushback if clinicians try to do imaging tests that may be more expensive than x-rays?
Dr Peiris: This is a good question, and it comes up when considering the cost of providing effective, efficient, high-quality care while ensuring that we're not inappropriately utilizing limited resources in our healthcare system. However, for most physicians, the cost issue is less of a concern than performing the right study that will provide the needed information to appropriately care for that patient.
Let's take head imaging for instance, which comes up regularly for children. If imaging is necessary for a head injury, the key issue tends to be to use the imaging modality that is most readily available and can be performed quickly and safely to provide the necessary information for diagnosis and management. Head CT or head MRI are options that may provide the necessary information, but each has trade-offs. For the purposes of this conversation, the key trade-offs are that head CT can be done quickly in most hospitals, with the appropriate personnel necessary to operate the scanner and interpret the study available at all hours; but CT exposes a child to ionizing radiation. Head MRI may take longer, and not all institutions have ready access to MRI scanners and personnel for study interpretation at all hours. And perhaps most important, a compromised child would have to hold still for relatively longer periods to acquire adequate images.
These are just some of the trade-offs physicians have to consider when choosing the right study for their patient.
Medscape: The guidance emphasized the importance of checking the patient history, to avoid duplication in testing. Could you elaborate further?
Dr Peiris: I, like many of my physician colleagues, have dealt with this in clinical practice far too often. Sometimes it is difficult to find out whether an exam was done, what type of exam was done, whether it was the right type of exam for the information that we need right now, and how long ago it was done. On top of that, if you know the exam was done, how do we get that information, especially if the patient is coming in from another city or from a different health system? Electronic health record management systems don't always speak to each other. These are bigger issues that we're certainly aware of and working on, but we recognize the concern. We don't want patients to have duplicate studies, but it happens.
Public Information from the FDA and Medscape
Information provided by FDA and/or its employees on this website is for educational purposes only, and does not constitute medical advice. Any statement or advice given by an FDA employee on this website does not represent the formal position of FDA. FDA and/or any FDA employee will not be liable for injury or other damages resulting to any individuals who view FDA-related materials on this website.
Cite this: Safety in Pediatric Imaging: FDA Releases New Guidance - Medscape - Jan 05, 2018.
