CT utilization--trends and developments beyond the United States' borders.

There has been an exponential rise in the use of CT during the last 25 years, with similar trending of data from regions across the world. However, variability in levels of utilization and patterns of practice in both adult and pediatric populations can be identified. Multiple technical, health care, regulatory and cultural factors are shaping our use of this modality. Surveys of pediatric CT dose are now available from several countries with the development of proposed diagnostic reference levels. Challenges of this process will be discussed. This short presentation is not intended as a comprehensive review of the infrastructure and numerous advances in pediatric CT radiation protection occurring around the world but aims to highlight a few aspects.