Fototoksičnost svetla – uticaj na oko

Abstract

Svetlost predstavlja jedan od mnogobrojnih oblika elektromagnet- nog zračenja čije talasne dužine leže u opsegu koji je u stanju da stimu- liše ljudski vizuelni sistem. Mnogobrojna istraživanja potkrepljuju tvrdnju da svetlost ima toksični potencijal i da može izazvati degenerativne promene i povrede, naročito mrežnjače, ali i ostalih tkiva oka (degeneracija makule, pterigijum, katarakta i dr.). Kao razlog navodi se upravo apsorpcija svetlosnih fotona različitih talasnih dužina, kako u rožnjači i sočivu (UV zračenje), tako i u RPE-u (delovi vidljivog spek- tra). U razmatranju fototoksičnosti najznačajniju ulogu ima štet- ni uticaj UV spektra na strukture oka ali plava svetlost vidljivog dela spektra ima energetske potencijale čiji su efekti kumulativni i koji mogu izazvati značajna fotohemijska oštećenja očnog sočiva, a posebno mrežnjače. Rožnjača i očno sočivo predstavljaju prirodne fil- tre za UV i plavo svetlo. Međutim, brojni su medicinski dokazi da ni ljudska rožnjača, ni sočivo, ne pružaju dovoljno zaštite od plavog svet- la modernog doba i da produženo izlaganje plavom svetlu može trajno oštetiti neke strukture oka. Smatra se da oštećenja nastaju kada prirodni regulatori bivaju „nadjačani“. Faktor plave svetlosti tre- ba da bude od maksimalne važnosti osobama koje imaju albinizam, afa- kiju, ahromatopsiju, kolobom, sub-luksirana sočiva, degeneraciju makule i druga stanja kod kojih svetlost stiže do mrežnjače bez filtriranja. Da bi se umanjili negativni efekti svetla na strukture oka po- trebno je imati odgovarajuću zaštitu u vidu sunčanih naočara ili odgovarajućih svetlosnih filtera.

Brightness represents one of many forms of electromagnetic radiation whose wavelengths lie in the range that is able to stimulate the human visual sistem. Many studies support the claim that the light has toxic potential and that it may cause degenerative changes and injuries, especially the retina, and the other eye tissues (macular degeneration, pterygium, cataracts, etc.). The absorption of light photons of different wavelengths is sited as the main reason, as in the cornea and lens (UV radiation), and in RPE-in (parts of the visible spectrum). In consideration of phototoxicity the most important role has harmful effect of the UV spectrum on the structure of the eye, but blue light of the visible part of the spectrum has energy potential whose effects are cumulative and could cause significant photochemical damage to the eye lens, especially retinal. Cornea and eye lens are natural filters for UV and blue light. However, there are a lot of medical evidence that neither the human cornea nor the lens, do not provide sufficient protection from the blue light of the modern age, and that prolonged exposure to blue light could permanently damage some structures of the eye. It is believed that the damage is created when natural regulators are “overwhelmed”. Blue light factor should be of maximum importance to people who have albinism, aphakia, ahromatopsy, coloboma, sub-luxated lenses, macular degeneration and other conditions in which light reaches the retina without filtering. In order to minimize the negative effects of light on the structure of the eye it is necessary to have adequate protection in the form of sunglasses or adequate light filters.