A recent issue of the New England Journal of Medicine contained an expert review on the health risks of radiation exposure from computed tomography (CT) (1). The article was authored by David J. Brenner and Eric J. Hall, from the Center for Radiological Research in New York. Brenner, in particular, is a leader in the field of research regarding the health effects of ionizing radiation from environmental, occupational and medical sources. Among his numerous publications are several research papers on radiation exposure associated with CT, as well as two books on radiation and health for the lay person.
In this latest paper, Brenner and Hall report data documenting an almost exponential increase in the number of CT examinations performed annually in the US, from 3 million in 1980 to an estimated 62 million in 2006. They note that the growth areas for CT are screening in asymptomatic adults and diagnosis in children, in whom currently 6%-11% of all CT examinations are performed.