gms | German Medical Science

Background: In order to prevent the retina from blue-light damage, yellow tinted, blue-light-absorbing intraocular lenses (IOL) are in broad clinical use. However, due to their transmission characteristics, a potential negative influence on the quality of vision under specific light conditions has been discussed. This study introduces a novel concept of a blue light filtering IOL with light-adaptive transmission (TA-IOL) and compares its possible protective effects to an untinted, UV-absorbing IOL regarding light-induced oxidative stress and growth factor expression in the human RPE.

Methods: A novel IOL, characterized by a central UV and blue light filtering zone, a surrounding transition zone and a clear, UV only absorbing periphery, has been designed. Then, primary human RPE cells were exposed to white light and either the TA-IOL or a UV-absorbing IOL was placed in the light beam. By using different apertures and intensities of light, bright and low light conditions were simulated. After 60 minutes of irradiation, cellular viability, induction of intracellular reactive oxygen species (ROS), and expression of vascular endothelial growth factor A (VEGF) were evaluated by a colorimetric assay, fluorescence microscopy and by RT-PCR and ELISA.

Results: Light exposure decreased RPE cell viability, and increased ROS and VEGF expression. These effects were significantly reduced by both, the TA-IOL and the UV-absorbing IOL. However, especially when bright light conditions were simulated, these protective effects were significantly stronger in presence of the TA-IOL, compared to the UV-absorbing IOL

Conclusion: In this study the novel TA-IOL demonstrated a significant better protection against light-induced oxidative stress and over-expression of VEGF than the UV-absorbing IOL. In addition, the presented concept of a TA-IOL may help to reduce potential negative influences of blue light filtering IOLs on the quality of vision under low light conditions.