Answer to Question #10638 Submitted to "Ask the Experts"

Category: Medical and Dental Equipment/Shielding — Shielding

The following question was answered by an expert in the appropriate field:

Q
I have worked in diagnostic and mammography for 37 years. Recently, I had cataract surgery. I was wondering if you feel the need for wearing lead glasses. I have been unable to find any information despite copious searches.

I have had really high doses due to not using thyroid shields nor lead glasses in 1970/1980/1990s. Our interns started wearing them post-2001, which actually led to technologists using them. It is sad, but "back in the day" that is how it was.

Also, in regard to wearing a thyroid shield (I have not had any thyroid tissues), should one wear a shield for lymph nodes in that region?
A

The latest International Commission on Radiological Protection (ICRP) recommendations (see http://www.icrp.org/docs/ICRP%20Statement%20on%20Tissue%20Reactions.pdf) indicate that the threshold dose for the lens of the eye is 0.5 Gy relative to cataract formation. In addition, ICRP indicates that the annual dose limit is 0.02 Gy, averaged over five years.

Cataract formation from radiation exposure is usually in the lens. If you have had cataract surgery and had the lens replaced, then the concern should be minimal relative to additional exposure to the eye.

Likewise, if there is no thyroid tissue, then the concern regarding additional radiation exposure should be minimal as it is the thyroid tissue that is sensitive to radiation, not the lymph system.

That said, it would be prudent to wear both if you are working in high-dose areas, e.g., interventional radiology, especially if you are in the position to set an example for others in those areas.

Joel E. Gray, PhD
Answer posted on 17 April 2013. The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.