Introduction to the PRIMA Device
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.
Understanding Age-Related Macular Degeneration (AMD)
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, these cells deteriorate and die, and people lose their central vision — meaning that an object straight ahead may appear blurry or covered up with a dark blotch.
Roughly 22 million people in the U.S. have AMD, and about 1 million have geographic atrophy, according to the American Macular Degeneration Foundation.
How the PRIMA Device Works
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 their 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 signals these cells send to be interpreted by the brain as vision.
An image processor, which the user must carry, lets patients zoom in and magnify the images they see, which appear in black and white.
Study Results and Patient Outcomes
With the help of the PRIMA device, 80% of the 32 patients who returned for a reassessment 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.”
Patient Experiences and Expert Opinions
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 receiving the implant was akin to “having two black discs in my eyes, with the outside distorted.” A self-described “avid bookworm” before losing her vision, Irvine said she was now able to do crosswords and read prescriptions.
Dr. Sunir Garg, professor of ophthalmology at the retina service of Wills Eye Hospital in Philadelphia, who was not involved in the study, said the results represent a breakthrough for patients with geographic atrophy. All doctors have been able to offer, he said, are visual aids, like magnifiers, and emotional support.
Dr. Demetrios Vavvas, director of the retina service at Mass Eye and Ear in Boston, who was also not involved in the study, said that the PRIMA system is not without limitations.
Limitations and Future Developments
Vavvas noted that the surgery required to implant the chip in the eye requires a high level of surgical skill and is not without risk. “You have to lift the retina off its normal position to implant this device, which increases the atrophy,” said Vavvas, who is a consultant to Sumitomo Pharmaceuticals, a company working on stem cell therapies for patients with other forms of vision loss.
New upgrades to the PRIMA device could be coming in the next couple of years.
The PRIMA system was invented by Stanford University ophthalmology professor Daniel Palanker and is being developed by the California-based neural engineering company Science Corporation.
Palanker said technical improvements are being made to increase the number of pixels in the chip from 400 to 10,000. The new chips have already been tested in rats, and the upgraded chips are being manufactured for future human trials. With the aid of the camera’s zoom function, Palanker said that this could theoretically enable patients to achieve 20/20 visual resolution.
Conclusion
The PRIMA device represents a significant breakthrough in the treatment of age-related macular degeneration, offering new hope to patients who have lost their vision due to this debilitating disease. While the device is not without limitations, its potential to restore vision and improve the quality of life for patients is substantial. Further research and development are needed to fully realize the potential of this technology, but the results of this study are a promising step forward in the fight against blindness.
FAQs
Q: What is the PRIMA device?
A: The PRIMA device is a tiny wireless chip implanted in the back of the eye, combined with specialized augmented glasses, designed to replicate vision in patients with age-related macular degeneration.
Q: How does the PRIMA device work?
A: The device works by capturing the visual field through a camera in the glasses, transmitting the image to the chip in the eye, which converts it into an electrical current that stimulates the remaining healthy cells in the macula.
Q: What are the potential benefits of the PRIMA device?
A: The device has the potential to restore vision and improve the quality of life for patients with age-related macular degeneration, enabling them to perform daily tasks such as reading and recognizing faces.
Q: What are the limitations of the PRIMA device?
A: The device is not without risk, requiring a high level of surgical skill to implant, and patients may experience side effects such as elevated blood pressure in the eye or accumulation of blood around the retina.
Q: What future developments can be expected for the PRIMA device?
A: Technical improvements are being made to increase the number of pixels in the chip, and future human trials are planned to test the upgraded device.
