Parents know to lather sunscreen on their children when playing outside in the summer for long periods of time. This is done primarily to prevent sunburn, but also to reduce the risk of future skin cancer. Some people are even aware that wearing sunglasses reduces the risk of melanoma formation on the eyelids. What is less known, is that similar to the skin, the eyes can get sunburned too. This condition is referred to as UV keratitis or Photokeratitis and describes a sunburnt cornea.
What is a Corneal Sunburn?
In the front of the eye exists a structure called the cornea. The cornea is a clear dome which bends light to be focused on the retina. Although the cornea is clear, the surface is composed of epithelial tissue just like skin tissue. Due to the similarity of the skin tissue to the corneal tissue, the cornea may get sunburned just like the skin does. Sunburns occur when someone is exposed to excessive UV light of 10-400 nm. Generally this is due to UV-A or UV-B radiation. UV-A and UV-B light is emitted from the sun as well as tanning beds, halogen bulbs, welding flames, snow reflections, and even some indoor light bulbs.
What are the Signs and Symptoms?
When an eye experiences UV keratitis or Photokeratitis, the eye usually will become painful about 4-12 hours later, similar to how long it takes for a sunburn to develop. You may also experience a feeling of something in your eye(s), grittiness, glare, blurred vision, light sensitivity, and tearing of the eye(s). The white part of the eye (sclera) may become red or pink in color. Usually both eyes are affected simultaneously by UV keratitis or Photokeratitis, but this is not always the case. One common way only one cornea gets sunburned is when someone drives a long time without sunglasses. The driver is exposed to more UV light in the left eye than the right eye because the side window on the left side lets more UV light into the car.
What should I do if this happens?
If you suspect you may have a corneal sunburn due to not wearing sunglasses while being exposed to UV light, see your nearest optometrist or ophthalmologist so they may help you. UV keratitis and Photokeratitis are easily treatable and generally cause no long term damage to the eye(s) or vision. Corneal sunburns are especially uncomfortable and yet another reason to always wear sunglasses when you are outside! Furthermore, people living at high elevation are at increased risk for corneal sunburns as are people with certain occupations (ex. welders). In addition to causing corneal sunburns, UV light may also cause cataracts, eyelid melanomas, retinal damage, and premature aging of the eyes.
Sources:
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5082247/
- https://my.clevelandclinic.org/health/diseases/15763-ultraviolet-keratitis
- https://eyewiki.aao.org/Photokeratitis