Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Retinal prosthesis trial completes first phase of testing

09.05.2003


One-year results presented at annual ophthalmology meeting



Researchers from the Keck School of Medicine of the University of Southern California, its Doheny Retina Institute and Second Sight, LLC, are reporting on the initial results of their groundbreaking, FDA-approved feasibility trial of an intraocular retinal prosthesis that appears to be able to restore some degree of sight to the blind.

"We have successfully completed enrollment and implantation of three patients in the trial," says Mark Humayun, M.D., professor of ophthalmology at the Keck School. "And we have found that the devices are indeed electrically conducting, and can be used by the patients to detect light or even to distinguish between objects such as a cup or plate in forced choice tests conducted with one patient so far."


The results are being presented at the Retinal Prosthesis I session of the annual meeting of the Association for Research in Vision and Ophthalmology, or ARVO, being held this week in Fort Lauderdale, Fla. Humayun, who is moderator of the session, is also presenting a paper detailing the results of the trial. In addition, he and his group from USC’s Doheny Retina Institute displayed six posters in sessions throughout the week. (Posters are embargoed until the time of their presentation.)

The microelectronic retinal prosthesis used in this first phase of the trial is intended to stand in for the damaged retinal cells in people suffering from such blinding diseases as retinitis pigmentosa and macular degeneration. The implant measures 4 millimeters by 5 millimeters, and is studded with 16 electrodes in a 4-by-4 array. The device has been developed by Sylmar, Calif.-based Second Sight, LLC: www.2-sight.com

The first participant in the trial underwent surgery to receive the implant in February of 2002. Patient #2 received the implant in July 2002, and patient #3 underwent surgery in March of 2003.

The retinal prosthesis-a sliver of silicone and platinum that is often incorrectly referred to as an ’eye chip’-is attached to and sits atop the retina. It works by electrically stimulating the remaining healthy retinal cells via the array of electrodes; the retinal cells, in turn, pass on the visual information to the brain via the optic nerve.

Initial tests in the three implanted patients have shown that they can perceive light on each of the 16 electrodes. Testing conducted so far in some of the patients with the microelectronic implant revealed that they were capable of detecting when a light is turned on or off, describing the motion of an object, and even counting discrete objects.

The first tests of the prosthesis in all three patients involved computer-generated points of light sent directly to the implant, says Humayun. Over time, they were ’graduated’ to images received by an external video camera. These images are sent to the intraocular electrode array attached to the retina via a receiver that is implanted behind the patient’s ear during the implant surgery. The signal is then recreated by stimulating the appropriate electrodes in the prosthesis.

Testing on the three patients is ongoing, says Humayun. "We plan in the near future to look at how useful the prosthesis can be in activities of daily living," he notes.


In addition to Humayun, the researchers involved in this work include Keck School researchers Eugene de Juan Jr., M.D., Douglas Yanai, M.D., Manjunatha Mahadevappa, Ph.D., Gretchen van Boemel, Ph.D., Gildo Fujii, M.D., and James Weiland, Ph.D., as well as Robert Greenberg, M.D., Ph.D., president of Second Sight, LLC, and other Second Sight scientists.

The National Institutes of Health/National Eye Institute and Second Sight, LLC, provided funding to support the research and development of the retinal prosthesis implanted in this trial. The National Science Foundation, the Department of Energy, the Office of Naval Research, the Whitaker Foundation, The Foundation Fighting Blindness, the Defense Advanced Research Projects Agency and Second Sight, LLC, have provided other funding toward the development of a retinal prosthesis.

For copies of abstracts online, go to www.arvo.org and click on the annual meeting link. Posters relating to this paper were or will be displayed in poster sessions 5056 (B715), 5059 (B718), 5060 (B719), 5079 (B738), 5081 (B740), and 5085 (B744); posters are embargoed until the time of their presentation.

Jon Weiner | EurekAlert!
Further information:
http://www.arvo.org

More articles from Health and Medicine:

nachricht NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures
17.11.2017 | National Institute of Standards and Technology (NIST)

nachricht High speed video recording precisely measures blood cell velocity
15.11.2017 | ITMO University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>