There are numerous ways that UV exposure can negatively affect our eyes and subsequently our vision. In some cases, this exposure many even lead to more serious conditions such as Photokeratitis, Pinguecula, Pterygium, Cataracts, and Macular Degeneration.
UV Light and Wavelengths
Before jumping into the conditions associated with UV light exposure, I thought I’d provide a quick refresher course on the types of UV light. Within the invisible light spectrum we have UVA, UVB, and UVC. Here’s the breakdown:
UVC is the most damaging to the skin. Thankfully, however, the majority of UVC is absorbed by the ozone layer and doesn’t reach us.
UVB affects the epidermis, or outer layer, of the skin. This results in sunburn, blistering, or possibly skin cancer. In relation to the eyes, it affects the corneas, or the clear front part of the eyeballs. This can cause severe irritation, light sensitivity, and lots of tearing. More on that later!
UVA is the one that penetrates the skin the most. This is because even though it isn’t as strong as UVB rays, it is more prevalent. UVA light makes up 95% of the UV radiation that reaches the earth and is the one that causes tanning and aging of the skin. But because it penetrates more deeply, it affects the inner layers of the skin and eyes.
Eye Conditions Associated with UV Light Exposure
Now that we’re up to speed, let’s talk about the specific effects these rays have on eyes. I will discuss them in order from short term exposure to long term exposure to the sun.
The first eye condition that can present from ultraviolet exposure is photokeratitis or ultraviolet keratopathy. Photokeratitis is a swelling or inflammation of the cornea, which is the clear front covering of the eye. One can experience many symptoms such as, redness, blurred vision, tearing, light sensitivity, or general pain of the eyes. This can result from a day at the beach or on the slopes and is usually a consequence of not wearing proper protection from the sun (i.e., sunglasses or a hat). It is also commonly referred to as snow blindness. Photokeratitis can also be seen in welders.
This is usually a temporary condition, but does require treatment with antibiotic and artificial tear eye drops to help it along. Cold compresses can also be used to help with the discomfort.
The second eye condition that can result from sun exposure is called a pinguecula. This presents as a white or yellow raised area or bump within the conjunctiva, which is the gelatinous layer that covers the white of the eye just outside of the colored part. This is particularly common in those who live in very sunny areas or even very dry, sandy, or dusty environments. This is not something that goes away once it presents itself, but can be treated if it becomes red or swollen with various eye drops. People with this condition should focus on using sunglasses or goggles for protection from the sun, wind, sand, or dust to prevent it from worsening.
The third eye condition is called a pterygium. With continued sun exposure, a pinguecula can grow from the white part of the eye onto the cornea, which is the clear front part of the eye. A pterygium is more obvious because it is a white, wedge or wing-shaped growth over clear tissue. If this continues to grow, then it may lead to scarring of the cornea, which could lead to permanent vision loss or distortion. If the pterygium is progressing, then surgery is required to remove it to save vision. This is a somewhat controversial procedure, in that pterygia have a high recurrence rate after removal. However, there have been some advances recently to help reduce recurrence by using other tissues of the eye or various compounds/agents during the removal procedure. This is a very common condition in those who live near the equator.
It is worth mentioning that although Pingueculas and Pteryhiums are related, they can present separately. Sun protection is once again the best prevention.
The fourth eye condition from long-term exposure of the sun (we are talking years of sun exposure), is a cataract. Though it is thought that we will all develop cataracts over time if we live long enough, there is evidence that those who have constant exposure to the sun, such as those close to the equator, will develop them more rapidly. Research is also showing that those who eat healthy diets in the form of green leafy vegetables, fruits, and antioxidants, and non-smokers are reducing the onset of cataracts. UV400 sunglasses are recommended for the best sun protection.
The fifth eye condition that can result from long-term sun exposure is damage to the retinal tissue or macular degeneration. The retina is the multiple layered lining of the inside of the eye. An area near the center of the retina is called the macula. The macula is where we get our central vision from and the area that provides the clearest vision. In macular degeneration the tissue composition within the macula begins to change. This causes loss of central vision resulting in blurred vision and eventually blank spaces in vision. This condition usually progresses slowly, but it can progress more quickly in some cases. This is most common in those 50 years of age or older, and there is evidence that those with macular degeneration have had more sun exposure throughout their life. There are various treatments for macular degeneration depending on the severity of the case, however, there is currently no cure. Treatment is used only to slow the progression, but cannot fix what has already been compromised.
These are just a few reasons to minimize sun exposure. There are other conditions from ultraviolet light that can affect the skin surrounding the eyes. In the meantime take these tips into consideration.
- Always wear sunglasses to protect your eyes when outside year round, i.e. UV400 sunglasses
- Wear wide-brimmed hats
- Avoid the sun during the hours between 10am-4pm
- Karpecki, Paul, OD. “The Role of UV Damage in Ocular Disease” Review of Optometry, Continuing Education. October 2012. University of Alabama School of Optometry and Essilor. 15 July 2015 http://www.reviewofoptometry.com/continuing_education/tabviewtest/lessonid/108520
- “Ultraviolet and Blue Light Aggravation Macular Degeneration” American Macular Degeneration Foundation. 15 July 2015 https://www.macular.org/ultra-violet-and-blue-light
- “Understanding UVA and UVB” Skin Cancer Foundation. 15 July 2015 http://www.skincancer.org/prevention/uva-and-uvb/understanding-uva-and-uvb
- “Facts about Age-Related Macular Degeneration” National Eye Institute. June 2015. National Institute of Health. 15 July 2015 https://nei.nih.gov/health/maculardegen/armd_facts
- Lippincott, Williams, & Wilkins. The Wills Eye Manual. Baltimore: Wolters Kluwer, 2008.