Light damage to the retina: an historical approach

Abstract

A brief review of retinal light damage is presented. Thermal damage requires a local rise in temperature of at least 10°C, causing an instant denaturation of proteins. The primary absorber is melanin. Photochemical damage occurs at body temperature and involves cellular damage by reactive forms of oxygen. The photosensitizers are photoproducts of the visual pigments. First indications that non-thermal damage might exist, in particular in the case of eclipse blindness, was presented by Vos in 1962. Attribution thereof to photochemical action was presented in 1966 by Noell et al who also measured the first action spectrum, in rat. It turned out to be identical to the absorption spectrum of rhodopsin. However, in 1976 and 1982 Ham et al found a quite different spectrum in monkeys, peaking at short wavelengths. The latter spectrum, but not the former, was confirmed since in numerous publications with animal models including rat. In ophthalmological practice a 'sunburn' was at first the only complaint caused by light damage. To avoid this, patients with dilated pupils should always be advised to wear sunglasses. Since the invention of the laser accidents have been reported, the most recent development is youth playfully pointing a strong laser pen in their eyes with marked consequences. The operation microscope and endoilluminators should always be used as brief as possible to avoid photochemical damage. Arguments for implant lenses that block not only the UV but also part of the visible spectrum seem too weak to justify extra costs.

Design and validation of a foldable and photovoltaic wide-field epiretinal prosthesis

“…A thin space of vitreous (100 µm) between the retina and POLYRETINA reduces the temperature increase by 0.009 °C, which is negligible. Thermal damage of the retina requires a local rise in temperature higher than 10 °C 33 ; the 50% of probability of retinal damage (ED50) has been previously defined for a temperature rise of 12.5 °C 31 . In our model, we estimated the ED50 with (red) and without (black) POLYRETINA (Fig.…”

IGF-1, Inflammation and Retinal Degeneration: A Close Network

“…Retinal degenerative diseases are heterogeneous pathologies; among them, age-related macular degeneration (AMD), retinitis pigmentosa (RP), and diabetic retinopathy (DR) have a high incidence and prevalence in humans (Hernandez et al, 2016 ; Narayan et al, 2016 ; Shaw et al, 2017 ). In fact, a plethora of factors including genetic alterations, aging, vascular defects, chemical insults, oxidative stress, or light-induced damage are responsible of the development of retinal degeneration (Semeraro et al, 2015 ; van Norren and Vos, 2016 ). In the pathologies associated to retinal degenerative diseases, progressive degeneration of the retinal neurons, predominantly in photoreceptors, retinal ganglion cells (RGCs), and cells of the retinal pigment epithelium (RPE), results in a severe deterioration of the visual function that in many cases leads to a complete blindness (Nazari et al, 2015 ).…”

Paradox response of cornea to different color intensities of visible light: An experimental study

“…Despite of the risk of exposure to visible light, but without it also has its risk. Phototoxicity of different visible light segments is well known [ 4 – 5 ], and it focuses on the retina with minor attention to the cornea. With the technological evolution, which includes devices such as smart phones and tablets, human life has become closely linked with this technology and, since it is difficult to quantify light exposure through everyday life, this study is devoted to clarify the possible interaction of corneal structural constituents with different light colors (wavelengths)/lux by recording and analyzing the vibrational characteristics using Fourier transform infrared spectroscopy (FTIR).…”