UV and The Eye:

Ultraviolet (UV) radiation comprises invisible high-energy rays from the sun and is believed to offer no benefits to the eye or vision in general. In fact UV radiation has been indicted in a number of eye conditions including the following: 

• Cataract   
• Pterygium – growth of tissue on the white part of the eye often extending over towards the cornea.  
• Corneal degenerations
• Eye Cancers – often on the lids or external tissues

UV radiation may also be indicated in Macular Degeneration.

Protection may be achieved by simple, safe and inexpensive methods such as wearing a UV filtering eyewear and a suitable sunhat / cap.

Who Is At Risk?

Anybody who spends long periods out of doors, either for work or leisure is at a higher risk of UV related eye problems. People who participate in activities on highly reflective surfaces e.g. skiing, sailing, fishing will be exposed to higher levels of UV radiation than normal. The risk is greatest during the mid-day hours, from 10 am to 3 p.m., and during the summer months. Ultraviolet radiation levels increase nearer the equator, so residents in these regions are at greater risk. UV levels are also greater at high altitudes.

Children are at a higher risk of sustaining ocular damage from UV radiation than adults. Children typically spend more time outdoors and their ocular structures are more permeable to UV radiation.

How To Protect Your Eyes

The effect of UV on the eye is thought to be cumulative i.e. mild UV exposure over a long period of time can gradually add up to cause problems later in life.

Ultraviolet radiation reaches the eyes not only from the sky above but also by reflection from the ground, especially from water, snow, sand and other bright surfaces. Protection from sunlight may be obtained by using both a wide brimmed hat or cap and UV absorbing eyewear. Good fitting wrap around sunglasses provide the most protection as they limit exposure to peripheral rays.

In an ideal world, all types of eyewear including prescription spectacles and contact lenses should filter the entire UV spectrum. A UV filter can be incorporated into all prescription spectacles. 

Not all sunglasses provide 100% UV protection. You should always choose lenses that block 99%-100% UV. Some manufacturers indicate 100% UV absorption by indicating " UV blocking up to 400nm". If there is no information label supplied with a particular pair of sunglasses ask for details of UV absorption properties from a staff member..

Photochromic lenses, those that darken outdoors may not provide full UV protection. UV absorption properties vary from one supplier to another, so again, if you have any queries ask a member of staff.

Sunglasses are graded in various categories according to the tasks for which they are most suitable. If you wish to do particular tasks or activities consult ask for advice from the practitioner / retailer.

Guide to buying sunglasses

Check the manufacturer label to ascertain details of UV protection.

Dark coloured lenses do not necessarily provide better protection.

Don't be misled by price - more expensive does not mean better protection.

Look for a well fitting frame with good coverage to minimise UV rays filtering in around the sides.

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