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no year exceeding 50 mSv. The current NRC limit is 7.5 times higher. It should be not-ed that these values have not been adopted by the NRC in the United States. Therefore, these recommendations are advisory rather than regulatory.

Recommendations for RadiologistsIn light of the ICRP recommendations, it

would be prudent for radiologists to under-take a few steps. Radiologists should review their radiation badge readings to see whether their annual doses are exceeding 20 mSv/y. This is shown on the badge report as eye dose equivalent. If the dose is close to or above the 20-mSv value, steps should be taken to re-duce the exposure. Some common steps to reduce exposure are to spend more time be-hind a shield that protects the eyes or to wear specific eye protection. There has been a re-cent review of eye protection [8]. Because ra-diation cataracts begin to form on the pos-terior pole of the lens, radiologists should inform their ophthalmologists that they are exposed to radiation to ensure that the poste-rior pole is examined.

References 1. Merriam GR Jr, Foct EF. A clinical study of ra-

diation cataracts and their relation to dose. Am J

Roentgenol Rad Ther Nucl Med 1957; 77:759–

785

2. U.S. Nuclear Regulatory Commission. Guide for

the preparation of applications for use of sealed

sources and devices for performing industrial ra-

diography: regulatory guide 10.6, revision 1.

Radiation Cataracts: New Data and New Recommendations

G. Donald Frey1

Frey GD

1Department of Radiology, Medical University of South Carolina, 171 Ashley Ave, Charleston, SC 29425. Address correspondence to G. D. Frey (freyd@musc.edu).

Res idents ’ Sect ion • Phys ics Minimodule

WEB This is a web exclusive article.

AJR 2014; 203:W345–W346

0361–803X/14/2034–W345

© American Roentgen Ray Society

For many years, it has been known that radiation can cause lens opacities commonly called radi-ation cataracts [1]. Until recent-

ly, it was believed that there was a high threshold for these events, and the radiation protection standards reflected this. The cur-rent Nuclear Regulatory Commission (NRC) limit for exposure to the lens of the eye is 150 mSv effective dose per year [2]. This limit was based on the suggestion that the thresh-old for cataract formation was 2 Gy for a sin-gle exposure [3]. Thus, it was commonly be-lieved that patients and radiologists were unlikely to develop radiation cataracts from routine procedures. Eye protection was only considered important for interventional radi-ologists and cardiologists.

In recent years, there have been a number of studies of astronauts [4] and intervention-al cardiologists [5, 6] that suggest that the ra-diation dose that can cause the formation of a radiation cataract is much lower than previ-ously thought.

International Commission on Radiological Protection Recommendations

These studies have led the Internation-al Commission on Radiological Protection (ICRP) to issue two new recommendations [7]. The first is that the threshold now be con-sidered to be 500 mGy, which is about four times lower than previously thought. The second is that the annual dose limit should be set at an average of 20 mSv per year, with

Keywords: radiation cataracts, radiation effects, radiation protection

DOI:10.2214/AJR.13.11242

Received May 16, 2013; accepted without revision May 18, 2013.

OBJECTIVE. This Minimodule discusses radiation cataracts and makes some basic sug-gestions for practicing radiologists.

CONCLUSION. For many years radiation-induced cataracts were considered unlikely by most radiologists. Recent data suggest that the likelihood is much higher than previously thought, and the International Commission on Radiological Protection has suggested lower exposure limits.

FreyRadiation Cataracts

Residents’ SectionPhysics Minimodule

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Code of Federal Regulation 10 CFR 20.1201.2.i.

December 1981

3. International Commission on Radiological Protec-

tion (IRCP) website. Annals of the ICRP: the 2007

recommendations of the International Commission

on Radiological Protection, publication 103. www.

icrp.org/docs/ICRP_Publication_103-Annals_of_

the_ICRP_37%282-4%29-Free_extract.pdf. Ac-

cessed June 19, 2014

4. Cucinotta FA, Manuel FK, Jones J, et al. Space

radiation and cataracts in astronauts. Radiat Res

2001; 156:460–466

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Radiatio-induced eye lens changes and the risk

for cataract in interventional cardiology. Cardiol-

ogy 2012; 123:168–171

6. Jacob S, Boveda S, Bar O, et al. Interventional

cardiologists and the risk of radiation-induced

cataract: results of a French multicenter observa-

tional study. Int J Cardiol 2013; 167:1843–1847

7. International Commission on Radiological Pro-

tection (ICRP). ICRP statement on tissue reac-

tions/early and late effects of radiation in normal

tissues and organs: threshold doses for tissue re-

actions in a radiation protection context. ICRP

publication 118. Ann ICRP 2012; 41:1–2

8. Struchio GM, Newcomb RD, Moletta R, Varkey

P, Hagen PT, Schueler BA. Protective eyewear

selection for interventional fluoroscopy. Health

Phys 2013; 104(2 suppl 1):S11–S16

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