Recent Developments In Nanotechnology And Wireless Electronics For Retinal Prosthesis
Retina implant technology attempts to restore the function of the light-activated cells found in the retina by implanting microelectronics and microchip electrodes surgically into the retina.
Nanovision Biosciences Inc. a start up based in La Jolla recently collaborated with engineers from the University of California San Diego with the aims of advancing research on restoring the ability of damaged neurons on the retina to respond to light.
The collaboration resulted in the development of a nanotechnology and wireless electronic for a new and more advanced type of retinal prosthesis. To demonstrate how it works the engineers made use of a rat retina, interfacing it with the prototype of the new technology in vitro.
It is a belief that this technology will help millions of people who suffer from eye-affecting neurodegenerative diseases. These diseases include retinitis pigmentosa which causes retinal degeneration and even macular degeneration which is one of the leading causes of vision loss.
The technology is also expected to help those who have lost their vision as a result of suffering from diabetes.
This most recent advance in retinal prosthesis is the latest in a series of advances made in the course of the last two decades.
Unfortunately, the devices that are already available to aid in the restoration of functional vision are still relatively limited regarding their performance. Nevertheless, these limitations are still within the central acuity threshold of 20/200. Anything below this threshold would still signal blindness.
According to one of the original founders of Nanovision Inc., Professor Gabriel Silva, the whole aim of the research was to come up with a more productive class of devices meant to improve the eyesight of people with impaired vision.
The technology developed in the collaboration between Nanovision Inc. and the University of California San Diego borrows from two revolutionary technologies.
The first of these is an array of silicon nanowires whose function is to sense light and simultaneously stimulate the retina. Unlike other prosthesis devices, this one provides a much higher resolution.
As a matter of fact, the closest research has gotten to recreate the close spacing present in the actual human retina.
The second technology that has heavily influenced this new retinal prosthesis technology is a wireless device whose function is to transmit data and power to the nanowires. The reception of transmission is over the same wireless link.
In addition to that, the speed of transmission is very high and it has higher energy efficiency levels.
Currently, the existing retinal prostheses use a vision sensor located outside the eye to capture visual scenes and subsequently change the view into an alternating signal which in turn, stimulate the retinal neurons.
However, this new prosthesis device uses silicon nanowires to imitate the light-sensing cones and rods located in the retina. This, in turn, stimulates the retinal cells.
Single wireless electronic signal powers the nanowires which are light activated and collectively joined into a grid of electrodes.
Furthermore, the device uses the power supplied to the nanowires to trigger high degrees of sensitivity in the light-activated electrodes and also control the timings of the stimulation.
It is important to note that this marks the biggest difference between existing prostheses devices and the recently developed device.