Radiologic technologists who have performed nuclear medicine (NM) procedures are at an increased risk of developing cataracts, according to a recent study published in Radiology.

The authors studied survey data from the years 2003 to 2005 and 2012 to 2013, analyzing the “work histories and cataract histories” of more than 42,000 technologists from the United States. They observed a “significantly increased risk of cataract” among technologists who have performed even one NM procedure in their careers.

“Risks of cataract were increased in the group who had performed a diagnostic or therapeutic NM procedure,” wrote lead author Marie-Odile Bernier, MD, PhD, of the National Cancer Institute in Rockville, Maryland, and colleagues. “Risks were higher for those who had first performed diagnostic NM procedures in the 1980s to early 2000s and those who had performed therapeutic NM procedures in the 1970s and in the 1980s to early 2000s.”

Previous studies have determined that medical workers are at a higher risk of developing cataracts, but Bernier et al. said their research was the first time such a connection had been established to NM procedures.

“The radiation doses to the eyes of NM workers are expected to be low because only photon emitters of low energy and/or beta emitters with energy levels higher than 0.7 MeV penetrate deep enough to reach the lens,” the authors wrote. “However, among NM workers, estimated annual radiation doses to the eyes have ranged from 0.9 to 25.0 mGy, depending on the type of procedure performed; these radiation doses could contribute to a relatively high cumulative dose after several decades of work.”

The authors did add that there is much more research to be done on this topic.

“Our finding of an increased risk of cataract in a population of NM workers should be interpreted with caution, as the exposure categories are based only on reports of working with these procedures and specific types of cataract were not available,” they wrote. “To confirm and quantify this relationship, the estimation of individual radiation doses to the eye lens from both occupational and personal medical sources should be a key focus of further study. Specific information about performing relatively high-dose NM procedures and assessment according to cataract type are also needed.”

The researchers noted that their study did have certain limitations, including the fact that cataract diagnoses were self-reported by the technologists in question, but they listed the large cohort size as a clear strength of their work.

Information on interventional cardiologists running an increased risk of developing cataracts can be found here.