Five questions for parents to ask about medical imaging

6 JUNE 2013

In light of more evidence of an increased risk of cancer associated with computed tomography (CT) scan in childhood or adolescence, NPS MedicineWise is advising parents that the overall risk is small and that health professionals will only consider medical imaging when it is justified.

A new Australian study investigating the risk of any cancer after a CT scan in childhood or adolescence has so far estimated one extra case of cancer for every 1800 CT scans, about 10 years after exposure.

The risk was highest after exposures in children younger than 5 and increased with each additional CT scan.

NPS MedicineWise clinical adviser Dr Andrew Boyden says that while the increase in cancer risk is relatively small, as a principle it is best to limit exposure to radiation from CT scans, especially in children.

“Medical imaging — including CT scans, x-rays and MRI — can be a very useful tool to help make or confirm a diagnosis or guide treatment decisions,” says Dr Boyden.

“But it should only be considered if the benefits for your child are likely to outweigh the radiation risks or other potentially harmful effects, and parents can be reassured that health professionals are well aware of these risks.

“A lot of the time, in situations such as mild sports injuries imaging won’t necessarily help — while at other times depending on the symptoms it can provide critically important information.

“In the situations where imaging is justified it is done using the lowest radiation dose possible. Modern scanners and imaging techniques are able to achieve this more readily than in the past, including with MRI scanning, which does not produce radiation.

If parents or individuals are unsure about medical imaging there are five questions they can ask for reassurance:

  • How will the imaging help my child’s condition or injury?
  • What does the imaging procedure involve?
  • Are there any risks associated with the imaging?
  • Are there any other options?
  • How much will the imaging cost?

There are also some other things parents can do if their child is going ahead with medical imaging.

“Parents can ask the staff at the imaging practice how they will minimise their child’s risk from radiation exposure or other possible harms from the imaging test,” says Dr Boyden.

“Helping your child relax is also important because movement can blur or disrupt images, especially with MRI. Helping your child stay calm and still may reduce the need for sedation or anaesthesia or for a repeat test in order to get a clearer image.”

NPS MedicineWise has information about medical imaging for children, including radiation risks, as part of a new information hub on imaging at


Independent, evidence-based and not-for-profit, NPS MedicineWise enables better decisions about medicines and medical tests. We are funded by the Australian Government Department of Health and Ageing.

Media enquiries: Stephanie Childs on 02 8217 8667, 0419 618 365 or or Erin Jardine on (02) 8217 8733 or