Who would have thought, only a few years ago. that it would be possible to give back sight to people who have become blind? For the first time, surgeons transplanted a retinal implant approved in Switzerland, called Argus II, to a visually impaired: a feat achieved on October 30 by a team of specialists in Lausanne, Switzerland. This prosthesis was implanted in a patient that became blind as a result of retinitis pigmentosa, a genetic disease. This is one of the most promising therapies intended to restore vision.
Revolutionary artificial retina
The retina of the eye is composed of light-sensitive cells, called photoreceptors. They convert light signals into electrical signals to stimulate the neurons. They are responsible for routing messages to the brain along the optic nerve. The photoreceptor failure impairs vision and can lead to blindness. To solve the problem, the surgeons implemented a few square millimeters implant on the patient’s retina. It contains electrodes which can stimulate cells that are still alive. Transmitted to the brain via the optic nerve, the information creates a perception of luminous forms that the patient must then learn to reinterpret to recover some vision. To function, the images are captured by a miniature camera installed in glasses. They are then sent to a small computer carried by the patient, which processes and transmits the signals to the implant via a wireless connection.
After a period of rehabilitation, the implanted patients – about 90 worldwide – see again, with a modest field of view. This treatment is designed for people whose photoreceptor cells degenerated but in which the nerve cells of the retina and optic nerve are still active. The vast majority of patients implanted can move independently, locate a door into a room or follow a line on the ground. In the best cases, they even manage to read words in large print on a black background