snow blindness. exposure to ultraviolet radiation (uvr) from the sun can lead to a “sunburn” of...

Snow Blindnes

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Snow Blindnes

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• Exposure to ultraviolet radiation (UVR) from the sun can lead to a “sunburn” of the cornea (clear surface of the eye).

• The intensity of ultraviolet energy increases by a factor of 4% to 6% for every 1,000 foot (305 meter)

depending upon the time of day and location

Snow reflects 85% of ultraviolet B Snow reflects 85% of ultraviolet B

dry sand reflects 17%

Reflex of ultraviolet BReflex of ultraviolet B

grass or sandy turf reflects 2.5%

Water may reflect 10% to 30%

symptoms may not become apparent for six to 12 hours

SymptomsSymptoms

SymptomsSymptoms Excessive tearing pain redness swollen eyelids pain when looking at light headache a gritty sensation in the eyes decreased (hazy) vision.

preventionWear wraparound sunglasses or glacier

glasses – darker lenses, – greater visible light filtration

– side covers. Keep them on even in overcast conditions, as UV rays can burn through thin clouds.

prevention If you lose your glasses, make emergency

"goggles" by cutting two horizontal slits in a piece of duct tape folded back onto itself; secure with tape.

Treatment

• patching the eye closed after instilling a few drops of phthalmic antibiotic solution (such as sodium sulamyd 10%, or gentamicin(

Treatment

» Remove contact lenses and avoid rubbing your eyes.

» Apply cool, wet compresses to help ease the burn, or take an oral pain medication like ibuprofen.

» Cover both eyes with half-inch-thick pads of soft cloth or

gauze bandages to protect them from light and prevent irritation

from eyelid movement.

Treatment

» Check the injury at half-day intervals. When you can keep your eyes open comfortably, remove the

dressing. Wear sunglasses whenever you are outside until your symptoms disappear completely.

» It's best to let your eyes heal before continuing your trip, but if conditions won't

allow for extra days, your hiking partner should lead you slowly down the trail.

Steroids

• Since snow blindness is self-limited, the application of a topical steroid is not imperative and best left to an ophthalmologist

The end