Not all Lightweight Lead Aprons and Thyroid Shields are Alike
OBJECTIVE: With the explosion of minimally invasive surgery, the use of fluoroscopy has significantly increased. Concurrently, there has been a demand for lighter weight aprons. The industry answered this call with the development of lightweight aprons. Our goal was to see whether lighter weight garments provide reduced protection. METHODS: Dry laboratory testing was performed in a standard X-ray room, using a standard fluoroscopy table and standard acrylic blocks. A commercial-grade pressurized ion chamber survey meter (Ludlum Model 9DP; Ludlum Measurements, Inc, Sweetwater, Tex) was used to detect gamma rays and X-rays above 25 keV. Nonlead aprons from several manufacturers were tested for scatter radiation penetration above the table at a fixed distance (3 feet) and compared with two standard 0.5-mm lead aprons of different manufacturers. RESULTS: Scatter measurements were made at 60 kVp and 70 kVp for pure lead (0.5 mm), mixed, and nonlead protective garments. Scatter penetration for the nonlead blends and barium aprons was 292% and 258%, respectively, at 60 kVp compared with the pure lead apron. At the higher beam quality of 70 kVp, the scatter penetration was 214% and 233% for the blend and barium aprons, respectively, compared with the pure lead apron. Our measurements demonstrate a noticeable difference in scatter reduction between pure lead and nonlead garments. Pure barium aprons and nonlead aprons from certain companies demonstrated scatter penetration that is inconsistent with the 0.5 mm of lead equivalence as claimed on the label. In addition, there was an incidental finding of a handful of lightweight aprons with significant tears along the seams, leaving large gaps in protection. Our study also demonstrates that several companies rate their lightweight garments as 0.5 mm lead equivalent, when actually only a small area on the chest and abdomen where the garment overlapped was 0.5 mm, leaving the rest of the garment with half the protection at 0.25 mm. CONCLUSIONS: Our reliance on protective lead garments to shield us from the biologic effects of radiation exposure and the inferiority of some lightweight garments necessitate a streamlining of the testing methods and transparency in data reporting by manufacturers.
Fakhoury, E., Provencher, J., Subramaniam, R., & Finlay, D. (2019). Not all Lightweight Lead Aprons and Thyroid Shields are Alike. Journal of Vascular Surgery, 70 (1), 246-250. https://doi.org/10.1016/j.jvs.2018.07.055