UV Light, Your Eyes and Contact Lenses

Most of us know the dangers associated with UltraViolet (UV) light to our skin, but many fail to recognise the dangers to our eyes. UV light can be linked to all number of eye degradation conditions that can cause the eye to deteriorate, damaging your vision. This type of eye damage can range from cataracts, macular degeneration, pingueculae, pterygia and photokeratitis all of which can cause temporary vision loss.
UV light is electromagnetic radiation but has a shorter wavelength than visible light. This makes it invisible to the naked eye but the risks are still very real. UV rays are found in sunlight as well as man made lights like the ones you find in sunbeds. UltraViolet light is divided into several different types based on the wave length, whereas some can be beneficial, providing us with vitamin D most can damage the human body.
Most mid-range UV light is prevented from entering the Earth's atmosphere by the ozone. High intensity light such as UVB (medium wave) is the main type of UV light that is thought to damage the eye. Over exposure to UVB light can cause photokeratitis (welder's flash or arc eye) which is linked to cataracts, pterygium and pinguecula which can form in the eye. These growths can not only be unsightly but can cause various corneal problems which may distort the vision.
UV light is absorbed through the eye molecules within the eyes own tissue and cells called chromophores in a process known as the absorption spectrum. Sun glasses provide a certain amount of protection, depending on the strength of the UV protection. Experts suggest that you should wear at least UV400 strength glasses which filter and reflect around 99-100% of UVA and UVB light with wavelengths of 400 nm. Although the European official standard is closer to UV380 with deflects up to 95% and is more widely available.
Prescription eye glasses are also becoming ever more common but contact lens wearers are at just as much risk when outdoors. Although most untreated contact lenses offer some UV protection it is often minimal. It is advisable for anyone who spends time outside to get eye protection such as sunglasses or UV treated Contact lenses as they are more at risk of over exposure to harmful UV rays. Ciba Visions Precision UV contact lenses are thicker than normal lenses. This makes the lens more durable than standard contact lenses. Precision UV also offer a wider range of lens powers than other contact lenses. They cover high minus up to -16.00 as well as high plus up to + 10.00. Johnson & Johnson's Acuvue contact lens range also offers some UV protection and are available from most contact lens shops.

Retour au blog