A Comparison of Ocular Radiation Exposure Utilizing Three Types of Leaded Glasses

Abstract

Introduction Minimally invasive spine (MIS) surgery has an increased reliance on fluoroscopic X-ray. Compounded radiation exposure to the surgeon has become increasingly concerning and ocular radiation has been associated with cataract formation. Leaded eye protection can reduce ocular radiation exposure. We evaluate the efficacy of three types of leaded eyeglasses during typical views of MIS spinal surgery. Materials and Methods Utilizing anthropomorphic patient and surgeon phantoms, radiation exposure to the lens of the surgeon phantom was measured. Four groups were analyzed: Group 1—no glasses (NO); group 2—lead lens without leaded sides (WOLS); group 3—lead lens with lead sides (WLS); group 4—sport wrap around leaded glasses (sport). A total of 15 individual 20-second exposures in the anteroposterior and lateral X-ray positions with phantom head positions at 0, 45, and 90 degrees were performed. All glasses were 0.75 mm lead equivalent. Radiation dose was measures using a solid-state dosimeter (Unfors EDD-30; Billdal, Sweden). Average radiation dose for each position, total radiation dose, and percent reduction to the lens was calculated for each pair of glasses. Student t-test was used to calculate significance. Results All three glasses (WLS, WOLS, and sport) had significant reductions in ocular radiation versus no glasses at all individual head positions ( p ≤ 1.31 × 10−34). Sport had a significantly lower ocular radiation dose than WLS at all positions except at 90 degrees AP (0.323 vs. 0.334, p = 0.001). Sport also had a significantly lower ocular radiation dose than WOLS in all cases except 0 degrees AP (0.376 vs. 0.285, p = 0.0003) and 90 degrees lateral (0.988 vs. 0.862, p = 7.38 × 10−28). WOLS had a significantly lower radiation dosage at all positions over WLS except at 45 degrees AP (0.286 vs. 0.279, p = 0.303). Average total radiation dosage was 36.47 µgray without glasses, 3.13 µgray for WOLS, 4.134 for WLS, and 3.32 µgray for sport. All glasses resulted in a significant reduction in total radiation dose over no glasses ( p ≤ 8.37 × 10−32). There was no statistical difference in the total radiation dosage of WOLS versus Sport ( p = 0.6) and both Sport and WOLS were significantly lower than WLS ( p = 0.009 and 0.003, respectively). Discussion Our study demonstrates a significant reduction in radiation exposure to the eye with all three types of leaded glasses. This study confirms other reports showing varying degrees of exposure with different angles and X-ray views. Furthermore, we show that contrary to intuition, leaded glasses with lead sides (WLS) may have adverse effects by possibly trapping radiation and increasing ocular radiation exposure. Based on our results, we recommend the use of sport-wrap type leaded glasses or those without lead sides (WOLS).