UV labelling for spectacles and contact lenses
The human eye is exposed to toxic Ultraviolet Radiation (UVR) from natural sunlight and man made artificial sources. UVR induced damage and related diseases can occur in a number of tissues within the eye, ranging from the corneal surface to the retina (Bergmanson and Söderberg 1995).
At the same time, the cornea and the crystalline lens provide inherent UVR protection (Boettner et al. 1962, Sliney 2002, Walsh et al 2008). Shading headwear and certain designs of UVR-blocking sunglasses can reduce UVR exposure but do not provide the high degree of ocular protection afforded by UVR-blocking contact lenses (Walsh et al 2003), particularly when the latter is combined with shading and sunglasses.
The design of UVR-blocking sunglasses and how they are worn are important in achieving optimal protection from these devices. Sunglasses providing a tight fitting wrap-around design, as opposed to small flat lenses mounted off the eye, offer the best protection to the ocular media, providing that they adhere to the highest standard of inherent UVR-blocker in their lens material (Rosenthal et al 1988, Leow and Tham 1995).
Well designed sunglasses also offer some protection for the eyelids and the bulbar conjunctiva.