University of Missouri Researcher Working with Retinal Implants to Make the Blind See
University of Missouri - Columbia
By U of M - Columbia Staff
In Star Trek: The Next Generation, Geordi La Forge is a blind character who can see with the assistance of special implants in his eyes. While the sci-fi character lives in the 24th century, people living in the 21st may not have to wait centuries for the illuminating technology.
Dr. Kristina Narfstrom, the University of Missouri-Columbia College of Veterinary Medicine's Ruth M. Kraeuchi-Missouri Professor in Veterinary Ophthalmology, has been working with a microchip implant to help blind animals "see."
Results are preliminary, but promising.
"About one in 3,500 people world-wide is affected with a hereditary disease, retinitis pigmentosa, that causes the death of retinal cells and, eventually, blindness," Dr. Narfstrom said. "Our current study is aimed at determining safety issues in regards to the implants and to further develop surgical techniques. We also are examining the protection the implants might provide to the retinal cells that are dying due to disease progression with the hope that natural sight can be maintained much longer than would be possible in an untreated patient."
Dr. Narfstrom is working primarily with Abyssinian and Persian cats that are affected with hereditary retinal blinding disease. The cat's eye is a good model to use for this type of research because it is very similar to a human eye in size and construction, so surgeons can use the same techniques and equipment. Cats also share many of the same eye diseases with humans. The Abyssinian cats that Dr. Narfstrom is working with typically start to lose their sight around 1- or 2-years-old and are completely blind by age 4.
To date, Dr. Narfstrom has performed surgeries in severely visually impaired or blind cats. During the surgery, Dr. Narfstrom makes two small cuts into the sclera, the outer wall of the eyeball. After removing the vitreous, which is the gelatinous fluid inside the back part of the eyeball, Dr. Narfstrom creates a small blister i 11/24/2007 crochip, which is just 2 millimeters in diameter and 23 nanometers thick. The chip includes several thousand microphotodiodes that react to light and produce small electrical impulses in parts of the retina.
"We are really excited about the potential uses for this technology and the potential to create improved vision in some of the millions of people affected worldwide with retinal blindness," Dr. Narfstrom said. "This technology may also be beneficial for pets that have similar diseases because this technology can benefit both animals and humans."
Dr. Narfstrom is working with Optobionics Corporation, the Naperville, Ill., based company that developed the device, and with Machelle Pardue, a researcher with Emory University and the Research Service at the VA Medical Center in Atlanta.