Striking a balance: Radiation not the only risk to consider when imaging pediatric patients

When managing the care of pediatric patients, both referring physicians and radiologists know to always consider the risks associated with radiation exposure. But according to a recent opinion piece published in Journal of the American College of Radiology, focusing too much on those risks and not considering other key factors can end up potentially harming the patient.

Lead author Mahadevappa Mahesh, MS, PhD, professor of radiology and cardiology at the Johns Hopkins University School of Medicine, wrote the piece with two other colleagues from the Baltimore school. The authors explained that, yes, many medical imaging procedures do expose patients to radiation, but radiation is just one of many things that must be considered.

“For instance, MRI does not use radiation and provides excellent tissue contrast but often requires anesthesia, especially for young children, because of its longer acquisition time,” the authors wrote. “Moreover, because of magnetic susceptibility at the air-tissue interface, MRI is also not the preferred modality for lung imaging. Fast-sequence MRI is increasingly being used, but it provides only limited information. Ultrasound is also being used more frequently, but it does not provide true 3-D imaging, and it can be operator dependent.”

Mahesh et al. also explain that advances in modern imaging technology have significantly lowered the amount of radiation exposure associated with different examinations. Hardware has been modified, software has been updated and protocols—particularly pediatric CT protocols—now have technologists using smaller doses with every scan.

Anesthesia, meanwhile, can still be quite dangerous to younger patients.

“Anesthetic in children can cause immediate adverse consequence that can range from minor effects such as dental injury, postoperative nausea or vomiting, and hypothermia to serious effects such as hypotension, hypoxia, cardiac arrest, and death,” the authors wrote.

To help make their point, the team turned to a recent example they had encountered while treating a two-year-old child with a severe case of pulmonary tuberculosis. CT studies were used to monitor the patient’s treatment, which did expose the patient to radiation. The dose was so low, however, that multiple scans were roughly equal to “less than three months of U.S. natural background radiation” or “a single screening mammographic examination.” Most important, the authors noted, the child never had to be sedated and the scans took just three seconds each. The care team had weighed the risks and benefits of their many options and made a decision they felt was best.

“It is judicious to assess each risk in pediatric studies and compare with the benefits that a particular method provides,” the authors concluded. “Physicians need to examine the benefits of medical radiographic imaging, including CT scans, in the pediatric population especially because low-radiation protocols are possible thanks to the technological advances mentioned here. Although ionizing radiation is not without risk, and studies that produce it should not be performed unless there are clear clinical indications, one should take into account all risks, including those due to anesthesia, and make informed decisions that provide the best clinical information with the least possible overall risks.”