by Rene S. Rodriguez-Sains, MD
For most of us, the eyes are the most cherished of our senses. Yet we potentially expose them to danger simply by going outside. Over time, the sun’s rays can seriously damage the eyes and surrounding skin, sometimes leading to vision loss and conditions from cataracts and macular degeneration to eye and eyelid cancers. However, simple daily protective strategies will help keep our eyes and the sensitive skin around them healthy.
Certain types of light from the sun can wreak havoc:
Ultraviolet A and Ultraviolet B light: Ultraviolet A (UVA) and ultraviolet B (UVB), powerful, invisible rays with wavelengths shorter than visible light, are the most dangerous parts of sunlight. They can cause cataracts, eyelid cancers and other skin cancers,1,2 and are believed to play a part in macular degeneration, a major cause of vision loss for people over age 60.3 In addition, UV rays can prematurely wrinkle and age the skin around the eyes.
High-Energy Visible Light (HEV light)/Blue Light: HEV light – high-energy visible light in the violet/blue spectrum is a potential contributor to cataracts and other serious eye maladies.1,2 Blue light can damage the retina over time, leading to macular degeneration. The retina is the membrane where images are formed and transmitted to the brain. The macula, the region of sharpest vision located near the center of the retina, is the most likely area to be damaged.
The fairer your skin, the greater your age, and the lighter your eyes, the higher your long-term risk, especially if your work or recreation involves prolonged sunlight exposure. Light eyes are at increased risk for skin cancer and certain eye diseases because they contain less of the protective pigment melanin.
But all of us are susceptible to these cancers or other conditions caused by the sun. We need to protect ourselves daily, because the damage keeps adding up.
Although designed to protect the eye, the eyelid’s skin is thin and contains many fragile tissues vulnerable to UV light. Inside the eye, the lens and cornea, both transparent, filter UV rays, but years of UV absorption can damage them. The lens, the eye’s focusing mechanism, can turn yellowish and cataractous. The cornea, the area in front at the outer layer of the eye, admits light and images to the retina. UV damage can cause:
Eyelid cancers: Eyelid skin cancers, including basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma, account for 5 to 10 percent of all skin cancers.4,5 Most occur on the lower lid, which receives the most sun exposure. BCCs make up about 90 percent and SCCs 5 percent or more of all eyelid cancers, while melanomas account for 1-2 percent.4-6
While BCCs elsewhere on the body rarely spread, eyelid BCCs potentially can spread to the eye itself and surrounding areas. SCCs grow faster and have greater potential to spread.
Both SCC and BCC are found mainly in patients with a long history of sun exposure,7 while melanomas are especially associated with intense, intermittent sun exposure and sunburns.
When diagnosed and treated early, eyelid cancers usually respond well to surgery and follow-up care, with the eye and eyelid largely retaining normal function. But left untreated, they can be dangerous. Watch for these early warning signs:
- a lump or bump that bleeds or does not disappear
- persistent red eye or eyelid inflammation that does not respond to medication
- new flat or elevated pigmented lesions with irregular borders and growth
- unexplained loss of eyelashes
If you have any of these signals, consult a skin cancer specialist or ophthalmologist, even if you feel no discomfort.
Intraocular melanoma: Although rare, it is the most common eye cancer in adults.8 It starts in the uveal tract, the middle layer of the eye containing the iris (the colored part of the eye) and choroid (the layer under the retina). Symptoms may include blurred vision and a change in the shape of the pupil (the dark area in the center of the iris).
Conjunctival cancers: Once rare, these have been rising rapidly in incidence, especially among older people. Incidence among white men increased 295 percent over a 27-year period.9-11 Melanomas of the conjunctiva, the protective membrane covering the outside of the eye and the inside of the eyelids, may be more common in patients with atypical mole syndrome;12 these patients sometimes have 100 or more moles, as well as one or more moles 8 mm (1/3 inch) or larger in diameter, and one or more moles that are atypical. All patients with cutaneous (skin) melanomas and/or atypical moles should have yearly ophthalmologic evaluations.
Cataracts: The most common cause of treatable blindness,13 cataracts are a progressive clouding and yellowing of the crystalline lens, the eye’s focusing mechanism. At least 10 percent of cataract cases are directly attributable to UV exposure,4 especially UVB. In the US alone, more than one million operations to remove cataracts are performed every year.4,14,15
Macular degeneration: Often referred to as age-related, or senile, macular degeneration, it is now believed to be caused by cumulative UV damage to the retina. The macula, the region of sharpest vision near the center of the retina, is the most likely area to be damaged. Macular degeneration is one of the major causes of vision loss in the US for people over age 60.3 Some studies point to UVA and HEV light as potential causes.1,2,16
Keratitis, or corneal sunburn:
Excessive UV exposure from the sun or tanning machines can burn the cornea, the clear refracting surface that admits light and images to the retina. Protective lenses are always advisable when you are exposed to UV. They are a must for skiers or snowboarders, since UV is more intense at high altitudes, and since snow reflects back about 80 percent of the sun’s rays, so that they hit your eyes a second time. Water and sand also reflect UV rays.17,18
Virtually all these conditions can be found during a routine ophthalmologist’s exam. Ideally, have a complete yearly exam, including dilated funduscopy.
Lenses that absorb/block UV offer strong defense against eye and eyelid damage. It’s best to wear sunglasses year-round in the sun.13 UVA light can damage the eyes and the skin around them throughout the year. Even on overcast days, UV can penetrate through clouds and haze.
Check if the glasses meet ANSI and/or ISO standards for traffic signal recognition, meaning they permit good color recognition.
Sunglass lenses come in many shades, with neutral gray, green, or brown usually offering the most comfortable vision. Choose the color that works best for you. Before purchasing sunglasses, check tags, labels, or packaging to make sure the lenses provide proper UV protection. For extra assurance, look for The Skin Cancer Foundation’s Seal of Recommendation.
For proper protection, sunglasses should offer the following:
- The ability to absorb and block 99 to 100 percent of UVA and UVB light. Ideally, they should also guard against HEV light.
- Sufficient size to shield the eyes, eyelids, and surrounding areas. The more skin covered, the better. Wraparound styles with a comfortable, close fit and UV-protective side shields are ideal.
- Durability and impact resistance.
- Polarized lenses to eliminate glare, especially when driving, but also out in the snow or on the water, where reflection greatly magnifies glare. Continuing glare can cause fatigue, headaches, and even migraines.
Other safety measures are also important.
- Wearing a hat with at least a 3” brim all around can block up to half of all UVB rays from your eyes and eyelids.13 Hats or tinted visors also help block UV from entering your eyes from above.
- Since sunglasses and hats cannot cover your entire face, sunscreen is also important.
- Finally, whenever outside, seek shade, especially between 10 AM and 4 PM.
Remember, practice all these strategies year-round — including when you’re on vacation, spring, summer, winter and fall.
Dr. Rodriguez-Sains is an ophthalmic plastic and reconstructive surgeon, ophthalmic oncologist, and ophthalmologist. He is a Clinical Assistant Professor at NYU-Langone Medical Center and a professional member of The Skin Cancer Foundation.
1. Implications of the blue light hazard and (ROS) in the pathogenesis of age-related macular degeneration, Dr. George Banyas, OD.
2. HEV Light and Macular Degeneration, Midwest Monthly, Vol. 5, Issue 3, March, 2008, http://mwlabs.cc/pdf/MMMarch2008.pdf.
3. National Eye Institute, National Institutes of Health, Age-Related Macular Degeneration, www.nei.nih.gov/health/maculardegen/armd_facts.asp
4. Rene S. Rodriguez-Sains, MD, The sun, the eyelids, and the eye, The Skin Cancer Foundation Journal, Vol. 23, 2005, pp. 36-7.
5. Eyelid basal cell carcinoma: non-Mohs excision, repair, and outcome, Hamada S, Kersey T, Thaller VT, Br J Ophthalmol, August 2005; 89(8): 992-994.
6. EyecareAmerica, The Foundation of the American Academy of Ophthalmalogy, Eyelid and Orbital Tumors.
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