New device offers hope to people blinded due to incurable eye disorders

November 17, 2013, American Academy of Ophthalmology

Research presented at the 117th Annual Meeting of the American Academy of Ophthalmology shows promising data about a device that helps people who have lost their vision due to a blinding genetic disease to recognize common objects. In the study, the researchers found when the objects' outlines had been enhanced, there was increased recognition. The device, called the Argus II, is the first FDA-approved retinal implant for adults with retinitis pigmentosa.

Retinitis pigmentosa is a group of genetic disorders that affect the retina's ability to respond to light. The disease, which is inherited and affects about 1 in 4,000 Americans, causes slow loss of vision, beginning with decreased night vision and loss of peripheral vision and eventually leads to blindness. Up to one-quarter of all patients with retinitis pigmentosa will become legally blind in both eyes. There is currently no cure for retinitis pigmentosa.

The Argus II retinal prosthesis is a system in which a miniature video camera is housed in the subject's glasses and sends information to a patient-worn video processing unit where the image captured by the camera is processed into instructions which are then transmitted wirelessly to a fitted with 60 electrodes. These electrodes pulse to stimulate cells in the retina, transmitting visual information along the optic nerve to the brain, creating the perception of patterns of light.

In the study, eight patients wearing the retinal prosthesis were asked to identify white or metallic objects against a dark background, then were asked to identify the same objects with enhanced outlines. The tests were done in three ways – with the turned on in a standard mode, in a scrambled mode as a positive control, and turned off as a negative control.

The results for solid object identification rose from 12.5 percent correct with the device switched off to 32.8 percent with the device on with 26.2 percent correct identification when the device was scrambled. Results for the outlined object identification were at 9.4 percent with the device turned off and 41.4 percent with the device on, with 20.7 percent correct identification in scrambled mode.

"Despite the small sample size, statistically the results have achieved significance due to the magnitude of change in the performance of the use of the device within each subject." said Yvonne Luo, MA, FRCOphth, of London's Moorfields Eye Hospital NHS Foundation Trust and lead researcher on the study. "Moreover, these subjects represent people with the most severe form of the disease."

The Argus II is the only device currently on the market in the United States and is one of several devices intended to help people suffering from this disease. Other devices and therapies in development include an implanted microchip, electrical stimulation therapy, implantable capsules of timed-release medication, nutrient therapies to reduce retinal damage and gene therapies to halt or reverse . Another study on this device will be presented on Monday and will review the initial results of a 30 subject study, adverse events post-implant, system reliability and visual function results.

Explore further: Researcher advances retinal implant that could restore sight for the blind

Related Stories

Researcher advances retinal implant that could restore sight for the blind

November 15, 2013
People who went blind as a result of certain diseases or injuries may have renewed hope of seeing again thanks to a retinal implant developed with the help of FIU's W. Kinzy Jones, a professor and researcher in the College ...

Eye implants make vision-restoring progress

July 18, 2012
(Medical Xpress) -- "I was blind once but now I can see.” The words are no longer the sole property of religious testimony and literature. Medical progress is being made in the restoration of vision as evidenced by Second ...

FDA recommends approval for Second Sight's Argus II retinal prosthesis system in the US

October 3, 2012
On Friday September 28, a U.S. Food and Drug Administration (FDA) Ophthalmic Devices Advisory Panel unanimously voted 19-0 that the probable benefit of the Argus II Retinal Prosthesis System outweighs the risks to health, ...

Retinal implants with wireless microchip restore functional vision in retinitis pigmentosa patients, research finds

February 20, 2013
(Medical Xpress)—Retina Implant AG, the leading developer of subretinal implants for patients blinded by retinitis pigmentosa (RP), announced results from part of its multicentre study were published today in the peer-reviewed ...

Wireless subretinal prostheses allows blind mice to see light

June 19, 2013
(Medical Xpress)—A team of researchers from the U.S. and Scotland has developed a new type of retinal prostheses designed to restore sight to blind patients. In their paper published in the journal Nature Communications, ...

Recommended for you

Bioengineered soft microfibers improve T-cell production

January 18, 2018
T cells play a key role in the body's immune response against pathogens. As a new class of therapeutic approaches, T cells are being harnessed to fight cancer, promising more precise, longer-lasting mitigation than traditional, ...

Weight flux alters molecular profile, study finds

January 17, 2018
The human body undergoes dramatic changes during even short periods of weight gain and loss, according to a study led by researchers at the Stanford University School of Medicine.

Secrets of longevity protein revealed in new study

January 17, 2018
Named after the Greek goddess who spun the thread of life, Klotho proteins play an important role in the regulation of longevity and metabolism. In a recent Yale-led study, researchers revealed the three-dimensional structure ...

The HLF gene protects blood stem cells by maintaining them in a resting state

January 17, 2018
The HLF gene is necessary for maintaining blood stem cells in a resting state, which is crucial for ensuring normal blood production. This has been shown by a new research study from Lund University in Sweden published in ...

Magnetically applied MicroRNAs could one day help relieve constipation

January 17, 2018
Constipation is an underestimated and debilitating medical issue related to the opioid epidemic. As a growing concern, researchers look to new tools to help patients with this side effect of opioid use and aging.

Researchers devise decoy molecule to block pain where it starts

January 16, 2018
For anyone who has accidentally injured themselves, Dr. Zachary Campbell not only sympathizes, he's developing new ways to blunt pain.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.