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 The end of pneumonia? New vaccine offers hope
23.10.2017 | University at Buffalo

nachricht Scientists track ovarian cancers to site of origin: Fallopian tubes
23.10.2017 | Johns Hopkins Medicine

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: Salmonella as a tumour medication

HZI researchers developed a bacterial strain that can be used in cancer therapy

Salmonellae are dangerous pathogens that enter the body via contaminated food and can cause severe infections. But these bacteria are also known to target...

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Symposium on Driving Simulation

23.10.2017 | Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

 
Latest News

Single nanoparticle mapping paves the way for better nanotechnology

24.10.2017 | Physics and Astronomy

A quantum spin liquid

24.10.2017 | Physics and Astronomy

Antibiotic resistance: a strain of multidrug-resistant Escherichia coli is on the rise

24.10.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>