Answer to Question #10638 Submitted to "Ask the Experts"
The following question was answered by an expert in the appropriate field:
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?
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.