A New Neuroprosthetic Device – The Argus II by Second Sight – Employs Retinal Implants To Project Images, Allowing The Blind To Read Braille Without Touch
Developed by Second Sight, the Argus II retinal implant streamlines braille patterns directly into a blind patient’s retina, allowing the blind patient to read four-letter words with an ocular neuroprosthetic device. The Argus II is a major breakthrough in Neuroprosthetics. The device has been implanted in over 50 patients, many of who can now see color, movement and objects.
The Argus II uses a small camera mounted on a pair of glasses, a portable processor to translate the signal from the camera into electrical stimulation. Such stimulation is generated by a microchip with electrodes implanted directly on the retina. What is impressive is that the majority of patients tested are able to incorporate the images and read quickly and accurately.
Authored by researchers at Second Sight, the study was published in Frontiers in Neuroprosthetics on the 22nd of November. “In this clinical test with a single blind patient, we bypassed the camera that is the usual input for the implant and directly stimulated the retina. Instead of feeling the braille on the tips of his fingers, the patient could see the patterns we projected and then read individual letters in less than a second with up to 89% accuracy,” explains researcher Thomas Lauritzen, lead author of the paper.
Based in the same innovative approach that led to cochlear implants, the visual implant uses a grid of 60 electrodes that are attached to the retina. The electrical impulses stimulate patterns directly onto the nerve cells. According to Silvestro Micera at EPFL’s Center for Neuroprosthetics, “this study is a proof of concept that points to the importance of clinical experiments involving new neuroprosthetic devices to improve the technology and innovate adaptable solutions.”
Primarily for sufferers of the genetic disease Retinitis Pigmentosa (RP), the implant Argus II has been shown to restore limited reading capability of large conventional letters and short words when used with the camera. The current study demonstrates how the Argus II can be adapted to provide a potentially faster method of text reading with the addition of letter recognition software in the future.