Is Ocular Safety in Orthopaedics Overlooked? A Systematic Review of Annual Ocular Radiation Exposure and Protective Measures
Authors: Arnold Keith E. , Whitmore Victoria , Hecht Christian J. , Porto Joshua R. , Kamath Atul F. 
Published: August 2024

Background
Intraoperative fluoroscopy is increasingly common in orthopaedics, although recent guidelines have reduced the maximum recommended exposure to 20 mSv annually. A systematic review of the literature was conducted to comprehensively assess current adherence to exposure guidelines, identify practice settings at increased risk for exposure, and determine the best practices and personal protective equipment for ocular radiation risk mitigation.

Questions/purposes
In this systematic review we asked: (1) Is the annual amount of eye irradiation received by orthopaedic surgeons below the recommended limit of 20 mSv? (2) What is the effectiveness of leaded glasses in reducing the eye’s exposure to radiation? (3) Which imaging setups and operative techniques reduce ocular irradiation?

Methods
PubMed, Medline, EBSCOhost, and Google Scholar were queried on September 28, 2023, to identify studies assessing intraoperative ocular radiation exposure among orthopaedic surgeons. Studies that measured radiation in or around the eye (such as the bridge of the nose or eyebrows) during orthopaedic procedures were included. Exclusion criteria were duplicate studies, studies that only estimated eye radiation based on the radiation dose recorded at parts of the body distant from the eyes, nonoriginal research, case reports, and articles without full-text English versions available. A total of 393 unique articles were retrieved, and after title, abstract, and full-text screening, 23 dosimetry studies were included, comprising 12 prospective observational studies, 7 phantom models, 1 cadaver model, 2 observational studies, and 1 randomized control trial. Risk of bias was determined via the Methodological Index for Nonrandomized Studies (MINORS) tool. Study quality was generally good to excellent, with noncomparative studies having a mean MINORS score of 14 ± 0 of 16 and comparative studies achieving a mean score of 19 ± 1 of 24, with higher scores representing better study quality. Due to extensive heterogeneity in study design, a meta-analysis was not conducted, with the results rather presented as a narrative summary of key findings.

Results
The vast majority of surgeons conducting a variety of orthopaedic and traumatologic procedures were not exposed to a hazardous level of eye irradiation annually, but surgeons who perform a high volume of fluoroscopy-intensive procedures may exceed guidelines. Leaded eyeglasses reduced eye radiation by about 90%, with sport wrap-around glasses offering better shielding than alternatives, although leaded glasses overall were largely underutilized. Positioning mini C-arms in the standard vertical configuration was shown to provide up to a 13-fold decrease in radiation exposure compared with inverted configuration, while standing perpendicular to the fluoroscope further reduced eye irradiation.

Conclusion
We found that orthopaedic surgeons who perform a high volume of fluoroscopy-intensive procedures may be at risk of exceeding recommendations on annual radiation exposure, although exposure can be mitigated through various simple strategies. In particular, this analysis found that the use of sport wrap-around leaded glasses, positioning of mini-C arms in the standard vertical configuration, and standing perpendicular to the fluoroscope provide the most effective means of limiting ocular radiation exposure. As ophthalmic radiation exposure presents a potentially important occupational health hazard to orthopaedic surgeons, further investigations of radiation exposure specific to high-volume, fluoroscopy-intensive orthopaedic practices and long-term ophthalmic outcomes will help determine the extent of the potential harm posed by frequent exposure to intraoperative radiation over the span of a career.

Level of Evidence
Level III, therapeutic study.