Artificial retinas: towards improved vision in patients with a rare genetic disease of the eye
Nov. 6, 2018
While retinal prostheses developed over the past ten years have enabled some blind people to perceive light signals again, their cost is high and the image they produce is not precise enough to recognize faces. In this study, researchers from the IGBMC (CNRS/Inserm/University of Strasbourg), the Institute of Chemistry and Processes for Energy, Environment and Health (CNRS/University of Strasbourg) and the Institute of Vision (CNRS/Inserm/Sorbonne University) in Paris used films of titanium dioxide nanotubes, a low-cost material, which would allow a fine adjustment of the stimulation of the retina neurons network. Results published online on October 18, 2018 in the journal Advanced Functional Materials.
The retina is a network of neurons, some of which, called photoreceptors, are sensitive to light. Photoreceptors capture light and transform it into electrical signals. After treatment by the rest of the retinal neural network, the visual information is sent to the brain. The death of photoreceptors leads to blindness, even if the rest of the network is not affected.
With three models in commercial use and others in clinical trials, artificial retinas are currently the most concrete approach to restoring visual perception to blind patients, particularly those with a rare genetic disease, retinitis pigmentosa. However, current systems are expensive to produce and require delicate surgeries, for restored visual acuity that remains below the legal threshold for blindness.
In this study, the researchers brought mouse retinas into contact with films of titanium dioxide nanotubes, a material well tolerated by the body and allowing effective stimulation of neurons. Thus, short and small light spots allow the retinal network to be activated up to a video frequency (25 Hz), even in the absence of photoreceptors, when they have degenerated.
Given their low cost and simple production, titanium dioxide nanotubes are a promising alternative to the artificial retinas produced so far and could improve the visual acuity of blind patients, especially those with retinitis pigmentosa.
This study was financed by the Regional Council of Alsace, Oseo, the ANR and the Cino and Simone Del Duca Foundation.