The eye and solar ultraviolet radiation: new understandings of the hazards, costs and prevention of morbidity
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This Position Paper is signed by an expert panel, comprising 11 optometrists, ophthalmologists, dermatologists, chemists, and physicists, that met in June 2011 for a comprehensive discussion of the dangers UV poses to the eye and ways to protect the eye from UV. The goals were to:
- Delineate what is known and not known about the damaging effects of UV on the eye,
- Review the costs in terms of both dollars and morbidity of UV-induced eye disease, and
- Identify the stumsbling blocks to greater adoption of effective eye protection

courtesy of: www.espf.com
The idea that sunlight can be damaging to the eyes is not new—evidence of ultraviolet’s negative effects has been accumulating for over a century. Sunlight exposure has been implicated to varying degrees in a variety of ocular pathologies involving the eyelids, conjunctiva, cornea, lens, iris, vitreous, and possibly the retina. These ophthalmic conditions have been collectively described as “ophthalmohelioses,” the ophthalmic equivalent of dermatohelioses.¹,²
The evidence for a causative connection between ultraviolet (UV) light and ocular pathology ranges from strong to highly suggestive, depending on the disease state. In the case of pterygium, a common ocular disease with highest incidence in tropical, high-altitude, and highly reflective environments, sun exposure is the only scientifically proven risk factor, and the critical role of UV damage in pterygium pathogenesis is well established. On the other hand, while there is some evidence that UV exposure may play a role in the development of agerelated macular degeneration (AMD), that role has not been definitively proven.
There is no question, however, that UV exposure —particularly the cumulative effect of long-term exposure to sunlight—is damaging to the eyes. While dermatologists have done a superb job alerting the public to the hazards of exposing skin to UV, the general population—and even many eyecare professionals—remain somewhat uninformed about the ocular hazards of UV. The result has been a low level of interest in and knowledge about sun protection for the eyes.
This may stem in part from a lack of effective communication of what we already know about the ocular hazards of UV exposure. More important in the longer term, perhaps, are gaps in our understanding of eye protection and the absence of consensus on standards for eye protection—we have, for example, nothing like the sun protection factor (SPF) that could tell sunglass consumers how effectively their new eyewear will protect them. Yes, we know that some clear and most sunwear lenses will block transmitted UV below 350 nanometers (nm) from reaching the retina, but what that does not tell us is how much UV still reaches the eyes without passing through the lenses. So while sunblock lotion buyers know the relative protection one preparation offers versus another, there is no similar scale for buyers of sunglasses.
Similarly, while the UV Index can tell consumers how much solar UV to expect on a given day; as this report documents, even that is flawed as a measure of ocular UV exposure. While excess exposure to UV is clearly hazardous, the situation is complex—moderate exposure to sunlight is important, perhaps even necessary, for good health. In dealing with UV risk, we must be thoughtful and sophisticated, balancing beneficial exposure with the need to protect both skin and eyes from overexposure.³
In an effort to raise awareness about the serious risks of ocular sun exposure and what can be done about them, Essilor brought together an expert panel in June 2011, comprising 11 optometrists, ophthalmologists, dermatologists, chemists, and physicists, for a comprehensive discussion of the dangers UV poses to the eye and ways to protect the eye from UV. Our goals were to:
- Delineate what is known and not known about the damaging effects of UV on the eye,
- Review the costs in terms of both dollars and morbidity of UV-induced eye disease, and
- Identify the stumbling blocks to greater adoption of effective eye protection.
The high points of that wide-ranging discussion are reported here. One point came across with great clarity: we know that UV presents a serious hazard to the eye, but we have not found means to communicate that effectively enough to get the public or even the majority of eyecare practitioners to act on that knowledge. The goal of this work, then, is to inform and by that means to incite action to protect eyes from the very real dangers of long- and short-term solar injury.