High CT radiation doses affect patients worldwide

Over the past five years, more than 2 million patients around the world have received cumulative effective radiation doses equal to or more than 100 mSv, according to a commentary published July 18 in Physica Medica.

Madan Rehani, PhD, of Massachusetts General Hospital in Boston and Michael Hauptmann, PhD, of Brandenburg Medical School in Neuruppin, Germany, classified 35 countries into categories of low, medium, and high numbers of patients per 1,000 people receiving cumulative radiation doses equal to or higher than 100 mSv on CT exams. Of these, two were classified as low (0 to one patient per 1,000 people), 24 as medium (one to two patients), and nine as high (two or more patients).

The authors found that the estimated total number of patients with cumulative effective dose equal to or greater than 100 mSv for all 35 countries combined over a five-year period was approximately 2.5 million out of 1.2 billion, or 0.21%. When the data were expressed as high dose per 1,000 people, the range was dramatic, from 0.51 per 1,000 in Finland to 2.9 per 1,000 patients in the U.S. -- a sixfold difference, Rehani and Hauptmann noted.

Those nine countries with the highest number of patients who received radiation doses equal to or more than 100 mSv on CT over five years per 1,000 people included Belgium, France, Iceland, Japan, Korea, Luxembourg, Portugal, Turkey, and the U.S.

"There is an urgent need for various stakeholders including medical physicists, referring physicians, health policy makers, manufacturers of CT equipment and epidemiologists to attend to the issue in the interest of patient radiation safety," the authors concluded.