Ocular Surface Ophthalmoheliosis in a Region of Patagonia

Abstract

The term helioses derives from the Greek root “hēlíōsis” which means excessive exposure to sunlight, a mixture of radiation with wavelengths ranging from 200nm to 4000nm, which comprises Ultraviolet Radiation (UVR), visible light and infrared light [1]. UVR has been found to reach diverse ocular components and is strongly absorbed by the anterior structures of the eye [2]. The cornea absorbs UVR differentially, based on the incident wavelength. More than 90% of UVR-C and UVR-B are absorbed by this ocular structure, as well as 60% of UVR-A [3], while the rest of the UVR-A is absorbed by the crystalline, with less than 1% reaching the retina [4]. Absorbed UVR is an important source of stress for the ocular surface through direct photo-oxidation (or type I). Also, indirect photo-oxidation (type II) can occur and produce Reactive Oxygen Species (ROS), which damage protein, lipids and cellular DNA [5-8].