Author: Grzegorz Łabuz, Rotterdam Ophthalmic Institute, University of Murcia
According to global statistics, about 10 million people annually undergo cataract extraction with implantation of an intraocular lens (IOL). The blue light filtering IOLs are thought to be an important protector of the visual system against a blue-violet light. However, there has been some controversy regarding the extent of benefits which these IOLs might provide.
The blue-violet light is defined as a range between 380 nm to 500 nm of spectrum of light and is called a blue light. It is thought that exposing the eye to the blue light is harmful for the ocular tissue and debilitates the eye’s condition. It has been shown that the high intensity of the blue light yields to thermal damage of the retinal cells, and as a consequence, its necrosis. Although, exposure to s small dozen blue light might also result in chronic toxicity and trigger an oxidant stress. Because the retinal photoreceptors and the retinal pigment epithelial cells (RPE) are the most vulnerable to the oxidant stress, the long exposure of the retina on the blue light might increases the risk of occurrence AMD or pigmentary retinophatis. The vulnerability of RPE to the light phototoxity is caused by the accumulation of lipofucins. The light absorption peak of lipofuscin is at 440 nm, which stays behind the phototoxity of the blue light for the RPE.
On the other hand, the blue light exposure also has a good influence on our live. The discovery of the 3rd retinal photoreceptor has shown that the blue light is responsible for the circadian rhythm. The disturbance of the circadian psychological function might leads to insomnia as well as mood disorders. The blue light also guarantees a better scotopic perception by stimulation of the rods in low light conditions.
Therefore, the potential benefits and side effects should be carefully reviewed when considering implantation of the blue light filtering IOLs.