X-rays for Imaging Children: How Much Do We Know about Benefits and Risks?

Imaging represents an integral part of today‘s diagnostic algorithms. Children differ in many aspects from adults – anatomy. physiology, metabolism and in general by the limited ability to adopt and compensate external environmental changes. Referring to the hazards of imaging the following topics can be identified: ionizing radiation, Gadolinium retention after contrast enhanced MRI and Doppler Ultrasound in small babies. In this lecture the focus will be put on ionizing radiation.

The increased radiation sensitivity of children, as compared to adults, can be explained by the fact, that children grow and maturate with corresponding higher cell turnover rates as well as the different distribution of red bone marrow. During cell division, cells are more prone to DNA damage by radiation. Other factors like the smaller mass absorbing radiation contributes to the higher radiation sensitivity too. The most worse scenario of radiation caused side effects is increasing cancer risk. Due to the long intervall of about 15-30 years this is beyond the observation of an individual physician.

Due to the many advantages of ionizing radiation based imaging modalities, like plain films or Computed Tomography (CT), their usage as dramatically increased over the last decades. Especially CT has become the major trouble solver in many clinical situations but accounts to about 50% of population based cumulative radiation burden. One should consider, that according European Union directive Euratom 97/43 the sequence indications - justification - dose limits must be kept. The ALARA principle (As low as reasonable achievable) is a wonderful acronym describing the process and was already published more than 100 years ago.

Moreover this directive also points out, that always imaging not using ionizing radiation have to be used first as well as procedures and exposure settings must be optimized for children. For those adjustments specialized knowledge and skills are needed like in other fields of medicine.

Today hazards of ionizing radiation can be visualized and quantified by immunflourescence techniques. The above mentioned challenges and risks will be discussed as well as an overview of today‘s most, ionizing radiation based examinations will be given.

Besides the above mentioned topics the psychological stress during examinations should be mentioned, especially in enviroments targeted to adults and not to children. Thus underlying the necessity of Pediatric Radiology as an own subdiscipline working in dedicated organisational units.

In conclusion, imaging is “problem solver” in many clinical situations, but can harm – in particular if settings are not optimized for children and radiation is applied by non dedicated staff.