A high number of veterans of the wars in Afghanistan and Iraq have sustained eye injuries, prompting the U.S. Army to fund research projects for prosthetics that can improve or return sight.
The U.S. Army Medical Research and Material Command announced three projects have been chosen for further development that may lead to some measure of healing for soldiers whose sight has been damaged, and eventually other patients whose sight has been damaged by injury or disease.
About 13.5 percent of Army veterans who sustained battlefield injuries during the two wars have sustained an eye injury, with approximately 1,100 soldiers undergoing surgery for significant eye damage after injuries ranging from lacerations and burns to direct blast injuries and blindness, according to the Department of Defense’s Congressionally Directed Medical Research Programs.
Last May, the CDMRP announced it would award $1 million for projects aiming to repair or restore sight to veterans injured in the wars, which has led to the selection of three that show promise.
“This is only the beginning,” Dr. Kenneth Bertram, principal assistant for acquisition at the USAMRMC, said in a press release. “Some obstacles and direction will be found through the studies of these prototypes. Our initiative is to restore vision and improve the quality of life for our wounded warriors and other Americans who have become blind.”
Dr. Joseph Rizzo, a researcher at Massachusetts Eye and Ear who has worked on the Boston Retinal Implant Project, is working on a wireless, implantable neural prosthesis that bypasses a patient’s damaged optic nerve and stimulates the lateral geniculate nucleus. This is a main part of the brain’s visual processing pathway, and would mean patients do not need to have a working optic nerve in order to have sight restored.
Researchers at the Roski Eye Institute at the University of Southern California are working on a technique to help improve the images relayed to the brain’s visual cortex through a cortical visual prosthesis.
The prosthesis stimulates nerve cells, though the process can be inaccurate and pollute sight with multiple spots of light appearing in the visual field because electrodes implanted in the brain do more than they should. The research team is working on methods of improving this process with its grant from the USAMRMC.
The third project, under development by researchers at the University of Maryland School of Medicine Center for Biomedical Engineering and Technology, is a synthetic neurotransmitter molecule that could be activated by light, helping it reach a small light-emitting device on the surface of the brain to activate neurons and help the brain create an image for sight.
Although all three projects are in their early stages, Bertram said the expectation is for better prosthetics to be developed and sight to be restored in injured veterans.
“When the eye and optic nerve are severely damaged, the hope of a cortical visual prosthetic is that by directly stimulating the brain’s visual cortex, it can restore sight,” Bertram said. “We are very pleased that the initial funding brings us three different approaches to the development of visual prostheses.”