Snow blindness, also known as photokeratitis, is an anterior segment eye condition resulting in the temporary loss of vision from intense exposure to ultraviolet (UV) rays. It usually occurs when UV light reflects off snow covered surfaces when proper eye protection isn’t worn, causing ‘sun burnt’ eyes. Photokeratitis can also be caused by looking directly at the sun as well as UV reflection off of water or sand.
With winter weather here, it’s the perfect time for a discussion about snow blindness, its prevention and treatment. Snow reflects 80% of UV rays from the sun and at higher altitudes (where skiing and other winter sports usually take place), UV rays are even stronger and exposure greater.
Snow blindness rarely results in permanent damage to the eye, but it is a painful and uncomfortable condition that causes intermittent vision loss and further photosensitivity. It’s easy to prevent with a few simple measures.
What is Snow Blindness?
When the cornea and conjunctiva are exposed to intense UV light, they become damaged and inflammation follows. This is a similar idea to the inflammation experienced by skin when it suffers from a sunburn. This inflammation causes pain as well as a variety of other symptoms in the eye.
Common snow blindness symptoms are:
- Burning, red, or watering eyes approximately 24 hours after the UV exposure
- Blurry vision
- Sensitivity to light (photosensitivity)
- Swollen, sore eyes and/or eyelids
- A feeling that something is ‘in’ the eye, like sand, or a gritty feeling
- A glare and halo around lights
- Eyelid twitching
Snow blindness symptoms and pain will get worse in the hours after exposure, just like a sunburn. When you’re hitting the slopes this winter, you won’t often notice the symptoms until you’ve finished for the day. Once you feel the effects of photokeratitis, the damage has been done. Prevention is key so you don’t suffer from these symptoms.
Preventing Snow Blindness
Snow blindness is very easily preventable with just a little bit of extra equipment when you’re skiing or snowboarding. Wearing eye protection that incorporates UV blocking lenses is the best and easiest way to prevent photokeratitis.
Wearing snow goggles (also known as ski goggles) that block out 100% of UV rays is the most common solution for snowboarders and skiers. They are tight fitting with side shields and wraparound protection to cover the eye from all angles. Glacier goggles are another good option. These are like sunglasses, so not as tightly fitting as ski goggles, but also offer wraparound protection to prevent UV rays from hitting the sides of the eye. Glacier goggles are made specifically for alpine and polar environments. They’re also polarized, giving you clearer vision in various light conditions.
Some contact lenses are made with UV protection. This is a great benefit, but when it comes to the risk of snow blindness, these contact lenses are not enough as they don’t protect the whole eye or eyelids, but do guard the cornea, crystalline lens and retina. Contact lenses don’t protect the conjunctiva or eyelids. The conjunctiva is the thin, clear mucous membrane that covers the white (ie. Sclera) connective tissue of the eyeball.
Snow Blindness Treatment
Your eyes will typically heal themselves from photokeratitis within 2 to 3 days. Very rarely is there permanent eye damage from snow blindness. However, in the days following exposure, your vision can be significantly impaired, with both your eyes and eyelids swollen and in pain, often making it hard to keep them open and function.
The best snow blindness treatments are:
- Apply frequent preservative-free artificial tear lubricants
- Stay indoors, preferably in a dark room if you are experiencing light sensitivity, and/or wear dark sunglasses
- Don’t wear contact lenses until the condition has been resolved
- Apply cold compresses to the eyes
- Avoid rubbing your eyes
- Topical anti-inflammatories or antibiotics may be prescribed in severe cases
- Use OTC oral pain relievers
Usually, these treatments will reduce the severity of symptoms and pain associated with photokeratitis and speed up the resolution of the condition.
When UV light is exposed to the eye through a reflection on snow, especially at high altitudes, snow blindness can set in quickly. UV light also poses other risks to the eyes that have more permanent damage, like eye or eyelid cancers, pterygium and cataract formation, and macular degeneration. Even though the effects of snow blindness may not be permanent, ensuring you use eyewear to protect against it will keep your eyes healthier in the long term.
Contact Us Today
Contact Dr. Jeff Sciberras for more information about photokeratitis and maintaining your eye health during the winter.