The number of medical examinations in which children are exposed to relatively high radiation doses has increased significantly over the last years. For example, the number of CT scans in children has risen by approximately 80% since 2005. A similar rise is also seen among adults, as is shown by research of the Dutch National Institute for Public Health and the Environment (RIVM).
An important motivation for this research has been the publication of the results of a large epidemiological study in 2013 that investigated the risks for children exposed to ionising radiation. That study shows that the cancer risk for children who have had a CT scan is larger than has been assumed previously.
It is well known that children are more sensitive to ionising radiation than adults. This is because children have more rapidly dividing cells and a longer life expectancy, so that radiation effects have more time to emerge.
Child protocols
This RIVM study shows that hospitals use different practices. In children’s hospitals child protocols are being used for radiological examinations, whereas this is not always true in general hospitals. There are also differences in radiation protection measures that are being taken.
In approximately half of all hospitals the employed doses are not being compared to the so-called Diagnostic Reference Levels (DRLs) for children. These DRLs indicate acceptable doses for adequate radiological imaging. Radiology department are not obliged to conform to the DRLs.
For a comparison of doses to a DRL a minimum of 20 children is required. Many hospitals do not receive that many children per type of examination. In hospitals that do perform a comparison, DRLs are exceeded in one out of five cases.
Recommendations
The causes of the rising number of examinations in children are unknown. It is important to investigate this further. The small number of comparisons to the DRLs and the regular exceedance of these also require further attention. Apart from this, RIVM advises to share the knowledge of children’s hospitals with the general hospitals so that all hospitals employ state-of-the-art paediatric radiology when examining children.
For this investigation a literature study has been conducted and a survey has been sent to all seven children’s hospitals and to 22 general hospitals in the Netherlands.