(Courtesy of Examiner.com) By implanting an experimental electronic eye device, the sight of a woman previously blind from retinal disease was partially restored. The woman is able to see light and make out figures for the first time in 20 years, explained lead researcher Lucian V. Del Priore, MD, PhD, an Attending Surgeon at NewYork-Presbyterian Hospital and a Professor in the Department of Ophthalmology at Columbia University College of Physicians and Surgeons.
The implant is currently being considered for the treatment of retinitis pigmentosa, a progressive disease that causes cell death in the outer layer of the retina – the area of the eye responsible for detecting light. In a healthy person, the cells in the outer layer of the retina detect light and then send a signal to the brain. In a person with retinitis pigmentosa, the outer layer of the retina does not transmit any signal to the brain. The person cannot see any light and cannot tell, for example, if his or her eyes are open or closed.
In patients with retinitis pigmentosa, the cells in the inner layers of the retina still function so the electronic eye implant is used to bypass the damaged cells in the outer layer of the retina and connect with the healthy nerve cells in the inner retina. The device works as a three-part system. The first part is an external video camera that is mounted on a pair of eyeglasses worn by the patient. That image is processed and then a signal is transmitted wirelessly to the second part of the system – a microprocessor (a small computer chip) implanted on the outside of the eye under the lid. This microprocessor then translates the information into a series of electrical pulses that are sent to the third part of the device: a tiny patch of 60 electrodes implanted near the deeper, healthy cells in the inner retina. From here, the electrical impulses trigger nerves in the inner retina and then send the image to the brain. The images that a patient can see are very basic. However, for a patient who has had no vision initially, the level of vision afforded by this device can represent a remarkable improvement, Dr. Del Priore said.
