UV-Related Eye Conditions
Cataracts: a cataract is the name given to the cloudiness of the eye’s lens that develops over many years’ exposure to UV light. Cataracts eventually impede vision. While most cataracts are age-related, some people are born with them. They may also result from injury, infection, metabolic disorders (such as diabetes) or use of certain drugs such as NSAIDs.

Treatment of cataracts involves surgical removal of the lens. This is a routine, painless procedure that restores clarity of vision. A plastic lens is slipped into place during the operation and this takes on the eye’s focusing function.

Age-related macular degeneration (AMD): AMD is the most common cause of irreversible blindness in Canadians of 65 and over. The condition is caused by the degeneration of the macula - a small area in the centre of the retina that facilitates detailed vision. AMD results in a gradual distortion and sometimes the complete loss of central vision. There is no known treatment that can reverse this vision loss.

Photokeratitis: This is the term given to sunburn of the cornea caused by overexposure to UV light. Photokeratitis almost always results from not wearing eye protection when outdoors on a sunny day. Snowblindness is a form of photokeratitis, caused by UV light reflecting off the bright surface of snow or ice.

Photokeratitis can be extremely painful for one or two days and can result in temporary loss of vision. Treatment involves covering the eyes, applying cool compresses, and taking an analgesic such as ASA or acetaminophen to reduce pain.

Protecting Your Eyes
You can protect your eyes from UV damage by wearing glasses with broad spectrum (UVA/UVB) protection. A wide-brimmed hat will further protect the eyes.

Whenever possible, choose glasses that have a wraparound design, to reduce UV light entering from the temple area. While polarization and photochromic darkening are desirable features for certain light conditions, they do not in themselves provide protection against UV light.

Many eye specialists now recommend that all glasses, including prescription glasses, be treated with a UV filter.

Choosing Sunglasses
The types of light most likely to injure your eyes are UV light, bright or intense light, and blue light, which is visible light in the blue portion of the colour spectrum. The intense glare of light reflecting off snow or water contains blue light.

A good pair of sunglasses will protect your eyes against damage from UVA and UVB rays, bright light, and blue light. Choose sunglasses with lenses that are dark enough to make your eyes feel comfortable, but not so dark as to obscure vision. If you spend time in bright sunlight bouncing off snow or water, select glasses that block out blue light and UV light. Medium to dark lenses with a grey, brown or green tint will filter out most blue light.

UV Protection Standards
It is impossible to tell from the price of a pair of sunglasses, how much UV protection they provide. However, since manufacturers of sunglasses follow voluntary industry standards when labelling their products, you should look for information that defines the use for which the sunglasses are intended.

The London Drugs UV Intensity Meter and Lens Tester will also show you if your glasses provide UVA/UVB protection. This card is provided in the sun care package given to customers who participate in any of our Sun Care Clinics, and may also be purchased at our stores.

Cosmetic sunglasses have lightly tinted lenses for use in sunlight that is not strong. They block from 0 to 60 percent of visible light and UVA rays, and between 87.5 and 95 percent of UVB rays. Cosmetic sunglasses are not suitable for driving.

General purpose sunglasses block from 60 to 92 percent of visible light and UVA rays and between 95 and 99 percent of UVB rays. These sunglasses are appropriate for driving and are recommended for use in sunshine bright enough to cause squinting.

Special purpose sunglasses block up to 97 percent of visible light and up to 98.5 percent of UVA rays. They also block close to 99 percent of UVB rays and are therefore suitable for prolonged sun exposure. These sunglasses are not suitable for driving.

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