Serviço de Radiologia, Hospital de Dona Estefânia, Centro Hospitalar de Lisboa Central
The increasing use of computed tomography (CT) in modern medicine has raised concerns regarding radiation exposure. While CT accounts for a small part of X-ray-based examinations, it delivers much of the total radiation dose associated with medical imaging. Radiation dose is particularly important in children because of the relatively increased lifetime cancer risk of children compared with that of adults. Therefore, several strategies have been assessed to reduce radiation dose for children.
The most effective way to reduce exposure to ionizing radiation is to avoid unnecessary medical examinations. It is very important to advise referring doctors about the appropriateness of CT, keeping in mind that the benefits must always exceed the harmful effects of radiation exposure. Triage patients toward the correct imaging test and, when possible, replace CT referrals for procedures with no ionizing radiation exposure, such as ultrasonography and magnetic resonance imaging.
When CT is performed, radiation dose levels should be the lowest possible to ensure diagnostic quality images. This could be achieved by using weight-based protocols, adapted to clinical indications and body region.