People with a leading cause of blindness were able to read again thanks to a tiny wireless chip implanted in the back of the eye and specialized augmented glasses, according to study results published Monday in the New England Journal of Medicine.
The trial involved 38 European patients, all of whom had an advanced stage of dry age-related macular degeneration (AMD) known as geographic atrophy.
There is no cure for AMD, which is driven by changes in a part of the retina called the macula and caused by inflammation and a build-up of waste. The photoreceptor cells in the macula are responsible for producing sharp, detailed and colored vision. When the disease has progressed to the geographic atrophy stage, the cells deteriorate and die, and people lose their central vision — meaning an object straight ahead may appear blurry or covered up with a dark blotch.
Roughly 22 million people in the United States have AMD, and about 1 million have geographic atrophy, according to the American Macular Degeneration Foundation.
In the study, the participants, who had an average age of 79, were fitted with the “PRIMA device,” a system meant to replicate vision. Patients wear augmented reality glasses embedded with a camera that captures their visual field. What the camera “sees” is transmitted to the chip implanted in the eye in the form of infrared light. The chip converts the light into an electrical current, which stimulates the remaining healthy cells in the macula in a realistic way, enabling the brain to interpret signals the cells send as vision.
An image processor, which users must carry, lets patients zoom in and magnify the images they see, which appear in black and white.
The image on the right shows what the camera sends to the user's implanted microchip. Science Corporation
With the help of the PRIMA device, 80% of the 32 patients who returned for reassessments one year after the chip implantation had achieved clinically meaningful visual improvements. Patients did experience side effects, predominantly related to the surgical procedure: The study reported that 26 serious adverse events occurred in 19 of the patients, ranging from elevated blood pressure in the eye to an accumulation of blood around the retina. The majority of the adverse events resolved within two months of the implantation.
“It’s the first ever therapeutic approach that has led to an improvement in visual function in this group of patients,” said Dr. Frank Holz, the trial’s lead investigator and chair of the department of ophthalmology at the University Hospital of Bonn in Germany. “Late-stage age-related macular degeneration is a dismal disease. Patients are no longer capable of reading, driving a car, watching TV or even recognizing faces. So [these results] are a game changer in my mind.”
One patient, Sheila Irvine, 70, who was fitted with the PRIMA device at Moorfields Eye Hospital in London, said in a statement provided by the hospital that her life before she received the implant was akin to “having two black discs in my eyes, with the outside distorted.” A self-described “avid bookworm” before she lost her vision, Irvine said she was now able to do crosswords and read prescriptions.
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