CT dose reduction in practice.

Greater than 10% of diagnostic imaging studies performed in developed countries are CT examinations. In the United States, as many as 60 million CT studies are performed each year, up to 7 million of which are performed in pediatric patients. In the spirit of the ALARA principle, both adult and pediatric radiologists should strive to decrease pediatric radiation exposure whenever possible. This can be achieved by utilizing imaging studies that do not require the use of ionizing radiation, thus decreasing the number of CT studies performed. If a CT study is indicated, the delivered dose should be optimized to use the lowest possible dose level while still answering the clinical question.