Light For The Blind: Artificial Retina Implant May Restore Vision To Millions
The creation of an artificial retina implant by scientists has brightened the hopes for millions of blind people to restore vision. The optimism has been buoyed by the retinal implant having helped mice to regain eyesight. The implant's trial in humans will start by end of 2017.
The retinal implant essentially helps in stimulating retinal neurons by converting light into electrical signals.
If the human trail turns successful, it will save millions of people from retinal decay to regain sight. Degeneration of retina is prominent with the "Retinitis Pigmentosa" disease which initiates the breakdown of photoreceptor cells to trigger blindness.
Retina, composed of millions of photoreceptors faces damage from mutated genes. That may happen even if the retinal neurons engulfing the photoreceptor cells are safe. Even in this condition, the retinal nerves will be intact making it possible to treat Retinitis Pigmentosa with bionic eye devices for achieving neuron stimulation.
The research has been published in Nature Materials.
In a new approach, the Italian Institute of Technology developed a retinal implant as a prosthesis based solution to replace the damaged retina.
"We hope to replicate in humans the excellent results obtained in animal models," said Grazia Pertile, one of the researchers, and ophthalmologist at the Sacred Heart Don Calabria in Negrar, Italy.
The lead researcher said the implant would be a turning point in the treatment of extremely debilitating retinal diseases.
The implant is basically a conductive polymer fixed on a silk substrate capable of absorbing photons when light enters the eye's lens. This results in electrical stimulation of the retinal neurons and makes up for the missing functions of lost and damaged photoreceptors.
Successful Testing In Mice
In testing the device, the artificial retina was inserted into the eyes of specially bred rats with retinal degeneration, which were then called Royal College of Surgeons (RCS) rats. This was done to ascertain the efficacy of retinal implant on RCS rats and also to differentiate them clearly while comparing with healthy rats and untreated rats.
When the tests on mice proved positive, the team inferred that the implant activates "residual neuronal circuitries in the degenerate retina," though more validation is required in explaining how the stimulation can work on a biological level.
The researchers also evaluated the sensitivity of rats to light called pupillary reflex, then compared the results with healthy rats and untreated rats.
Treatment For Cornea Condition
Meanwhile, a new treatment for the constraining eye condition Keratoconus has been having many takers. The treatment seeks to develop natural anchors in persons with weaker cornea area that struggles to maintain its normal dome shape. Often, the cornea bulges out and vision gets obstructed.
The method, known as Corneal Collagen Crosslinking, was approved by the FDA in April of 2016. Crosslinking works to enhance collagen crosslinks, which are the natural anchors in eyes.
"The goal is to basically bring a cornea that is a little bit pooching forwards and not as strong kind of more in a little bit, and make the cornea so it doesn't protrude as much," noted ophthalmologist Nicole Lemanski.
It is not a total cure but a way of improving vision and the results start to show in three months.
The curative process involves disinfection of the eye and its numbering followed by application of Riboflavin drops. The cornea is then exposed to ultraviolet light to allow the riboflavin to react with the ultraviolet light and oxygen in the air for creating new crosslinks.