High-Dose Radiation Imaging Guidelines Inadequate, Researchers Say

A common test to diagnose or stage patients with chest pain and breathing difficulty for heart disease is often done multiple times, exposing patients to potentially harmful, and perhaps unneeded doses of radiation, according to a report published Monday in the Journal of the American Medical Association.

The authors say that a single such myocardial perfusion imaging (MPI) exam has the highest radiation burden, "accounting for 22% of cumulative effective dose from medical sources." 

But these tests are frequently administered without regard for the number of prior tests performed, the interval between tests, the nature of any abnormal findings and whether any were inconclusive, according to the researchers, led by Andrew Einstein, MD, and colleagues at Columbia University Medical Center in New York.

"Future efforts need to focus not just on individual test justification, but on optimizing and validating longitudinal imaging strategies to lower cumulative doses while ensuring performance of imaging needed for therapeutic decision making," the researchers wrote.

Also, current guidelines for administering MPI are detailed, but "do not yet simultaneously consider the appropriateness" of exams that don't involve radiation, such as stress echocardiography, stress magnetic resonance imaging and exercise electrocardiography.

The researchers studied a cohort of 1,097 patients undergoing MPI tests at Columbia during the first 100 days of 2006 to evaluate how many tests they received and how much radiation.