When news outlets began reporting that a computer chip implant might restore some vision in people with age-related macular degeneration (AMD), several patients at the Sue Anschutz-Rodgers Eye Center at the University of Colorado Anschutz approached ophthalmologist Niranjan Manoharan, MD, about the experimental procedure.
AMD is a progressive eye disease that damages the retina, a layer of tissue near the back of the eyeball that detects light and transmits vision information from the eye to the brain. AMD is a leading cause of vision loss among older adults and its prevalence is growing. As of 2019, an estimated 19.8 million Americans aged 40 and older had AMD, according to the Centers for Disease Control and Prevention. The American Academy of Ophthalmology explains that one in five people with AMD are estimated to have geographic atrophy, an advanced form of AMD in which patients can lose a lot of their central vision.
“The trouble with geographic atrophy is the lack of effective treatments for it. If you’ve lost vision, there is nothing available to bring it back,” says Manoharan, an associate professor and director of informatics at the CU Anschutz Department of Ophthalmology. “That’s where the PRIMA implant came into play.”
The PRIMA device is a tiny wireless chip that is surgically implanted under the retina, aiming to replace the light-sensing cells that have been destroyed by AMD. After the procedure, patients are given a pair of glasses that has a small, embedded camera and projector. The glasses are designed to capture images in real time and send infrared light to the PRIMA implant. This activates the implant, which is made up of 378 light-powered pixels, to stimulate other cells in the retina called bipolar cells.
By stimulating bipolar cells, the device seeks to make the retina send signals of what the camera is seeing to the brain. The hope is that this process effectively restores some of the vision that patients with AMD have lost.
Though the procedure may be enticing to patients, Manoharan cautions that there is still much research to be done on the device before it can be an approved treatment option. We recently spoke with Manoharan, a retina specialist, about the potential of this device for treating AMD, current concerns, and the need for more research.
The following interview has been edited and condensed for clarity and brevity.