Snow blindness is a condition which is caused by the UV rays reflection from the snow and ice. It is important to protect your eyes from snow blindness, especially during winters. This article will tell you about the causes, symptoms, treatments and prevention of snow blindness.
Early TimesHundreds of years ago, before the modern protective eyewear was invented, Inuits and other tribal people, who dwelt in high altitude and snow-covered regions, used ivory, caribou antlers, bones or wood to carve snow eyewear for protection against snow blindness. Their goggles covered the eyes well, and blocked out most of the light rays.
Snow blindness is an eye condition that arises due to exposure of eyes to the ultraviolet rays of the sun reflected from an ice or snow. Medically, the term for snow blindness is photokeratitis and is akin to the burn of the cornea and conjunctiva. It happens when climbers go for hiking without protecting their eyes with sunglasses. The light that is reflected from the snow contains harmful and high levels of ultraviolet radiation. This radiation can burn the cornea of the eye and lead to snow blindness. Its symptoms like painful burning, blurred vision and irritation usually occur on the eye about six to twelve hours after intense sun exposure.
Snow blindness usually occurs at higher altitudes, where the ultraviolet rays are more intense. Basically, snow is a good reflector and can reflect about 80 percent of ultraviolet radiation. For this reason, skiers and hikers have greater risks to harm their eyes if appropriate eyewear is not used. Snow blindness has even higher probability of occurrence in Arctic and Antarctic regions. Snow blindness can also occur in anyone who involves in snowy outdoor activities like hiking, snowshoeing, or skiing.
Symptoms
- Impaired vision
- Sensitivity to bright light
- Seeing halos
- Small pupils
- Swollen eyelids and redness
- Watering of eyes
- Uncontrollable eyelid twitching and eye pain
- The eyes may swell shut due to extreme swelling
- Temporary loss of vision
- Burning sensation of the eyes that feels like as if sand particles or broken glass has entered the eyes
Treatment
▸ Avoid touching or rubbing the eyes during the healing process.
▸ Remove contact lenses to prevent any further damage so that the eyes recover faster.
▸ Stay indoors in a darkened room.
▸ Cover the eyes with pads of soft cloth or gauze bandages to prevent light from entering into them.
▸ Apply cold and wet compresses over closed eyes.
▸ Use prescribed ointments that are available to speed up recovery.
▸ Sterile artificial tears or anesthetic eye drops may be advised by a doctor.
▸ Over-the-counter pain killers like aspirin, acetaminophen or ibuprofen may help.
▸ If the condition is severe, see your doctor.
Prevention
▸ Snow blindness can be prevented by wearing 100% UV blocking polarized goggles, wraparound sunglasses or glacier goggles. These glasses transmits about 10% of visible light and absorbs almost all UV rays. They should have large and darker lenses, more light filtration, and side shields to prevent the eyes from light from all angles. Glacier goggles are same as sunglasses, but have extra features to block the light, like attachments on the sides and its bottom. They are usually made with mirrored, polarized lenses that are darker than regular sunglasses.
▸ Sunglasses or snow goggles should always be worn, even when the weather is cloudy, as UV rays can penetrate through clouds. A dark or mirrored lens one is always the best option. Snow goggles are vented at the bottom of the wrap-around, and not at the top. This allows the moisture to escape and thereby does not fog or freeze the goggles. They are also tight-fitting and offer full side coverage.
▸ A hat or a helmet should be worn with a visor to prevent the sun's rays from entering the eyes from above.
▸ In case of an emergency, a goggle can be made with a piece of tape, cardboard, bark or other material that is readily available. It can be used to cut a nose, and two thin horizontal slits at the point of vision that is just enough to see and prevent light from entering. It can be secured to one's face with a string or tape and wrapped around well to get the most protection.
▸ Blackening the eyelids with soot or charcoal can absorb some of the harmful UV rays, and divert the light away from your eyes.
▸ Get some eye drops or ointment for snow blindness from your doctor before going out in the snow.
▸ For people who wear contact lens, some brands of contacts are made with excellent UV blocking material. However, the protection is only limited to the corneas and pupils, and not the tissue of the conjunctiva or eyelids.
Always remember that prevention is always better than cure for anything. So, always keep your sunglasses handy to protect the eyes from UV rays.
