UV protection for the eyes: What patients need to know

Image credit: AdobeStock/Lyubov

Many people know that invisible UV light can cause a sunburn and contribute to skin aging and skin cancer, but there is less public awareness of the effects of UV radiation on the eyes. UV exposure has been associated with pterygium and pinguecula, skin cancer around the eyes, ocular melanoma, accelerated development of cataracts, age-related macular degeneration, and photokeratitis.¹

There are 3 types of UV radiation: UV-C (100-280 nm) is absorbed by the ozone layer and generally doesn’t reach the eyes (or skin). UV-B (280-315 nm) is absorbed primarily by the cornea, and UV-A (315-400 nm) reaches the lens and, in some cases, the retina. Although a damaged lens can be replaced in cataract/lens surgery, damage to the retina and macula can’t be repaired.

Figure 1. Younger patients are more susceptible to UV damage to the eye, but sun protection for all ages is critical. Image courtesy of Johnson & Johnson Vision.

Children’s eyes are especially vulnerable to UV radiation. Children tend to spend more time outside than adults do, and when outdoors, they are less likely to consistently wear sunglasses. Results from one study found that only 12.3% of children, compared with 41.6% of adults, wore sunglasses on sunny days in Hawaii.² Children have larger pupils than adults, allowing more light to reach the retina. Finally, the younger lens transmits a high proportion of UV-A rays, gradually declining as the biochemistry of the lens develops over time. By 1 estimate, the lens of an 8-year-old person transmits 75% of UV-A radiation, the lens of a 13-year-old person transmits up to 60%, and the lens of a 25-year-old person transmits less than 5% of UV-A rays (Figure).³ Perhaps not surprisingly, approximately 30% of children aged 9 to 11 years and more than 80% of people aged 12 to 15 years already have signs of UV-related ocular changes that can be detected by UV fluorescence photography of the ocular surface.⁴

Protecting the eyes

UV damage is cumulative and mostly irreversible in the eye, so it is never too late to start a comprehensive ocular UV protection strategy. That should include sunscreen, a wide-brimmed hat, and sunglasses. Sunglasses should block at least 99% of UV rays (UV-A and UV-B). The most effective sunglasses are wraparound styles that fit close to the face to minimize light coming in around the edge of the frames.⁵

Table. A categorization of the different UV-blocking contact lenses available on the market.

Vision correction choices can provide multiple layers of protection. Spectacle lenses typically offer UV protection in the material or as a coating. But most styles of spectacles only block light rays that come straight through the lenses. Peripheral light rays can still reach the eye around the side of the frames, just as with sunglasses.⁵ Increasingly, contact lens manufacturers are offering UV blocking in at least some of their contact lens brands. Class 1 UV blocking is the highest level of protection available, blocking at least 90% of UV-A and 99% of UV-B radiation (Table). Of course, although large-diameter UV-blocking contact lenses that cover the limbus protect all optical structures of the eye, the addition of a hat and sunglasses helps to fully protect eyelids, conjunctiva, and the skin around the eyes.

All intraocular lenses and spectacle lenses contain UV blockers, so it may seem surprising that UV blocking is not ubiquitous in contact lenses. A challenge for contact lens companies is that most use UV light to cure their lenses during the manufacturing process, because high-energy UV light is very efficient (think about the UV lights used in nail salons). Visible light–curing methods take more time, and reconfiguring a manufacturing line to accommodate an alternative curing method can be quite expensive. Lenses that also block some portion of the blue/violet visible light spectrum (in addition to UV) can be even more difficult to cure.

Talking to patients and parents

To introduce the topic, I like to ask patients an open-ended question: “What are we doing about UV protection for your eyes?” If they say they wear sunglasses, I ask them to put the sunglasses on so that I can observe how closely the glasses fit their face. If they don’t have the sunglasses on hand, I remind them that is part of the problem; sunglasses can only protect when they are worn. This is a good opportunity to remind patients that layering different methods of ocular sun protection can be helpful; when any layer is missing, the others still provide some protection.

In addition to talking about how to protect the eyes, I also talk to patients about when to protect their eyes from UV. Many people think about wearing sunglasses at midday, between 11 AM and 2 PM, especially if they are at the beach, pool, or another full-sun environment. It’s true that midday is the highest-risk time of day for the skin, but UV exposure for the eyes can be most intense in the morning and midafternoon,⁶ because the brows shade the eyes when the sun is directly above but are less effective at doing so when the sun is lower in the sky. Additionally, UV rays can penetrate cloud cover even when it is not sunny outside. Because of this, it is important to have 1 or more methods of UV protection on hand in all types of outdoor environments and at any time of the day and any time of year.

Parents understand and care about their children’s skin exposure to UV, so it isn’t a huge leap for them to understand that UV can also affect children’s eyes. However, they sometimes struggle to get their children to wear sunglasses and hats. The following tips can help children be more successful with UV protection:

• When introducing sunglasses to infants and young children, put the sunglasses on them when they are already outside in bright light. Even a very young child can appreciate the reduction in glare, which may help them overcome any irritation about the glasses on their face or around their head.
• For older children, consider Class 1 UV-blocking contact lenses to provide the highest levels of always-on protection in addition to sunglasses and a hat.
• Wear sun protection yourself. Children like to copy adults.

As health care providers, we should be talking about UV protection for the eyes as part of a comprehensive sun care strategy with all our patients.

References:

1. Taylor HR. The biological effects of UV‐B on the eye. Photochem Photobiol. 1989;50(4):489-492. doi:10.1111/j.1751-1097.1989.tb05553.x

2. Maddock JE, O’Riordan DL, Lee T, Mayer JA, McKenzie TL. Use of sunglasses in public outdoor recreation settings in Honolulu, Hawaii. Optom Vis Sci. 2009;86(2):165-166.doi:10.1097/OPX.0b013e318194eae7

3. van Kuijk FJ. Effects of ultraviolet light on the eye: role of protective glasses. Environ Health Perspect. 1991;96:177-184. doi:10.1289/ehp.9196177

4. Ooi JL, Sharma NS, Papalkar D, et al. Ultraviolet fluorescence photography to detect early sun damage in the eyes of school-aged children. Am J Ophthalmol. 2006;141(2):294-298. doi:10.1016/j.ajo.2005.09.006

5. Rosenthal FS, Bakalian AE, Taylor HR. The effect of prescription eyewear on ocular exposure to ultraviolet radiation. Am J Public Health. 1986;76(10):1216-1220.doi:10.2105/ajph.76.10.1216

6. Sasaki H, Sakamoto Y, Schnider C, et al. UV-B exposure to the eye depending on solar altitude. Eye Contact Lens. 2011;37(4):191-195. doi:10.1097/ICL.0b013e31821fbf29