Protective effect of light emitting diode phototherapy on fluorescent light induced retinal damage in Wistar strain albino rats

Background: Artificial light at night alters retinal physiology. Several studies have shown that light emitting diode phototherapy protects the retina from the damaging effects of acute light exposure. Objective: The aim of this study has been to elucidate the protective effects of 670 nm LED light on retinal damage induced by chronic fluorescent light in Wistar rats. Methods: Male Wistar albino rats were divided into four groups: group 1 were control (CL), group 2,3 and 4 were exposed to fluorescent-light (FL), LED preexposure + fluorescent light exposure (LL) and only LED light exposure (OL) respectively. All animals were maintained in their specific exposure regime for 30 days. Fluorescent light of 1800 lx was exposed between 8 pm to 8 am. Rats were exposed to therapeutic LED light of 670 nm of 9 J/cm(2) at 25 mW/cm(2) for 6 min duration. Histopathological changes in the retina were studied. Results: Animals of the FL group showed a significant reduction in the outer nuclear layer thickness and cell count in addition to the total thickness of the retina. LL group which were exposed to 670 nm LED prior to exposure to fluorescent light showed a significant decrease in the degree of damage. Conclusions: 670 nm LED light preexposure is protective to retinal cells against fluorescent light-induced damage. (C) 2014 Elsevier GmbH. All rights reserved.