Reviews Supplements Essilor CE October 2012 : Page 1

The role of Ocular Disease By Paul Karpecki, OD, FAAO ptometrists have long known the impact of ultraviolet (UV) light radiation that can result in cataract development, age-related macular degeneration and even pterygia or pingueculae. But these conditions continue to increase in prevalence even though many contact lenses, IOLs and spectacles have UV protection coatings. This paper looks at the latest understanding of UV expo-sure and some of the more com-mon as well as rare diseases that optometrists face when it comes to UV damage. Figure 1: A patient diagnosed with a conjunctival malignant melanoma. Damage in O UV Exposure and Ocular Health There are three forms of ultravio-let light—UVA, UVB and UVC. UVA has a wavelength of 315nm to 380nm and penetrates deeply into the skin. This is often associ-ated with tanning, but also is linked to skin aging. UVB has a wavelength that is even smaller, between 280nm to 315nm. UVB does not penetrate into the skin as deeply as UVA be-cause the epidermis mostly absorbs it. Thus, it can be a more damag-ing form of ultraviolet light that can cause erythema or sunburn, blistering of the skin, and potentially various skin cancers. UVC ranges from 100nm to 280nm in wavelength and is the most harmful to the skin, also resulting in skin cancer. Fortunately, most of it is absorbed by the ozone layer and does not reach the Earth’s surface. The sunlight that does reach the Earth is comprised of approximately 95% UVA light and 5% UVB/UVC. UVB and especially UVC are di-rectly absorbed by DNA molecules, so this is why experts believe that Supported by Sponsored by

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