High-Tech Glasses and Eye Implants Revive Vision Affected by Aging

Individuals experiencing significant vision impairment can regain the ability to read, thanks to a compact wireless chip implanted in one eye along with advanced glasses.

Age-related macular degeneration (AMD) is a prevalent condition that impacts central vision and tends to progress over time. While the precise cause remains unknown, this condition arises from damage to the light-sensitive photoreceptor cells and neurons located in the central retina, leading to difficulties in facial recognition and reading. Available treatments are primarily designed to slow down the progression.

An advanced form of AMD referred to as geographic atrophy typically allows individuals to retain some photoreceptor cells that facilitate peripheral vision, along with sufficient retinal neurons to relay visual information to the brain.

Leveraging this capability, Daniel Palanker and his team at Stanford University in California created the PRIMA device. This system includes a small camera mounted on the glasses, which captures images and projects them through infrared light onto a 2-by-2-millimeter solar-powered wireless chip implanted at the rear of the eye.

The chip then transforms the image data into electrical signals, which the retinal neurons transmit to the brain. Infrared light is employed for this process as it is invisible to the human eye, thereby ensuring it does not interfere with any remaining vision. “This allows patients to utilize both the prosthesis and their peripheral vision simultaneously,” explains Palanker.

To evaluate its efficacy, researchers enlisted 32 participants aged 60 and above, all suffering from geographic atrophy. Their visual acuity in at least one eye was below 20/320—meaning they could see what a person with 20/20 vision could see at 320 feet (97.5 meters) only at 20 feet (6 meters).

The team initially implanted a chip in one of the participant’s eyes. After a waiting period of four to five weeks, the volunteers began using the glasses in their everyday activities. The glasses enabled them to magnify their view up to 12 times and adjust brightness and contrast as needed.

After a year of using the device, 27 of the participants managed to read again and recognize shapes and patterns. They also noted an average improvement of five lines on a standard eye chart compared to their initial findings. Some participants were able to achieve 20/42 vision.

“Witnessing them progress from reading letters to full words brought immense joy to both sides. One patient expressed, ‘I believed my eyes were irreparably damaged, but now they’re revitalizing,'” shares Jose Alan Sahel from the University of Pittsburgh School of Medicine.

While stem cell therapy and gene therapy may potentially restore vision lost due to AMD, these approaches are still in early experimental trials. PRIMA stands out as the first artificial eye designed to restore functional vision in individuals with the condition, allowing them to perceive shapes and patterns.

Approximately two-thirds of the volunteers experienced temporary side effects, such as increased intraocular pressure, as a result of the implants; however, this did not hinder their vision improvement.

“This research is both exciting and significant,” remarks Francesca Cordeiro from Imperial College London. “It provides hope for delivering vision improvements that have previously seemed more like science fiction.”

The improved visibility experienced by participants is limited to black and white. “Our next objective is to develop software to provide grayscale resolution and enhance facial recognition,” states Palanker. Nevertheless, researchers do not anticipate achieving color vision in the near future.

Palanker also aims to increase PRIMA’s resolution, which is currently constrained by pixel size and the total count that can be included on a chip. Testing a more advanced version in rats is underway. “This current version equates to human vision of 20/80, but electronic zoom can enable vision as sharp as 20/20,” he explains.