Snow blindness is a painful eye condition caused by exposure of eyes to the ultraviolet (UV) rays. It happens when the eyes are insufficiently protected by sunglasses or googles. Snow blindness doesn’t only affect those who live in the polar regions; it can also affect anyone who enjoys snowy outdoor activities such as hiking, snowshoeing, or skiing. In these conditions, the sun’s ultraviolet rays can burn the cornea of the eye, causing snow blindness, which may not be noticed for several hours after intense sun exposure.
The symptoms are painful, gritty sensation in the eyes. The eyes may be red and watering, the eyelids may be twitching and the person will not want to look at anything bright. Like sunburn to the skin, the signs and symptoms usually start a few hours after the sun exposure. Snow blindness may cause a temporary loss of vision, or even permanent vision loss in extreme cases of repeated exposure.
How is it treated?
- Prevent further injuries, so do not rub the eyes, remove contact lenses.
- Wear sunglasses and stay in darkened room
- Use cool, wet compresses over closed eyes
- Painkiller taken by mouth can help
- Sterile artificial tears or anaesthetic eye drops may be advasied by a doctor
- Medical help may be needed
Snow blindness can be prevented by using sunglasses or eye protection that transmits 5–10% of visible light and absorbs almost all UV rays. Additionally, these glasses should have large lenses and side shields to avoid incidental light exposure. Sunglasses should always be worn, even when the sky is overcast, as UV rays can pass through clouds.
Source: Mountain First Aid Course of HealthFirst