Eye Health Central

What is Snow Blindness?

What Is Snowblindness?

Contrary to its name, snowblindness doesn't actually cause blindness, and it isn't strictly related to snow. Although, the two are commonly related to one another, which is how the condition originally got its common name. It is caused by overexposure to UV sunlight, which can happen in extremely bright outdoor environments, especially those where sunlight has a high chance of reflecting off of a surface before reaching the eyes. This includes bodies of water, sandy beaches or deserts, and of course, snowy areas.

The condition, known medically as photokeratitis, is usually quite painful, as the damage caused by UV light is very much like that of a sunburn. It also causes a loss of vision, which may either be temporary, or permanent, depending on the severity of the damage.

The part of the eye that is most affected by photokeratitis is the cornea, the thin, clear lens in the front of the eye that focuses the incoming light onto the retina. Because it is the first eye tissue that incoming light comes in contact with, it is bombarded with all of the UV light. This means that while it does protect some of the other tissue within the eye from damage, it does suffer quite a lot of it on its own.

what is snowblindness

Common activities that often result in snowblindness include water skiing, snow skiing, snowboarding, mountain climbing, and boating. The water's surface can be very reflective, but snow can reflect even more light. Additionally, the sun's UV light is even more intense at higher elevations, as there is less atmosphere to absorb it as it travels. This means that snow skiers are at a double risk of developing snowblindness while on the mountain.

People have likely been suffering from snowblindness for thousands of years, as they trudged through the snow in winter, or across the sand in the desert. But only in recent history have people gotten photokeratitis from man-made sources of UV light. Anyone who doesn't wear proper eye protection while using a tanning bed, welding equipment, or powerful black light UV lamps is at risk of snowblindness.

Once a person has photokeratitis, the following symptoms are likely to present:

  • Appearance of glare and halos around light sources
  • Blurred vision
  • Headaches
  • Redness
  • A sensation of a foreign object in the eye
  • Sensations of pain or burning of the eyes
  • Sensitivity to light
  • Swelling of the eyes or eyelids
  • Watery discharge

These symptoms usually only last a couple of days. During that time it may not be safe to go about normal daily activities, such as driving, as the effect that photokeratitis has on vision can make it difficult to clearly see the road and other divers.

Despite the high level of discomfort commonly associated with the condition, little to no medical treatment is necessary. Pain medication can be taken to manage any discomfort, and contact lenses should not be worn until the eyes have fully healed. Also, eye drops can be helpful in soothing the eyes and reducing any burning sensations. Finally, placing a cold, damp cloth over closed eyelids is comforting, too. 

Sunglasses are highly effective, both in treating photokeratitis once it's occurred, and in preventing it in the first place. Make sure to wear sunglasses that offer strong UV protection, as some glasses are simply tinted for fashion purposes, and don't protect the eyes at all. 

Author: John Dreyer Optometrist Bsc(Hons), MCOPTOM, DipCLP
Created: 10 Apr 2018, Last modified: 20 May 2024