We are truly living in a miraculous time when it comes to the advancement of medical technology, however, it’s also kind of spooky at the same time. Is there really any limit to what we can accomplish through the help of technology, an open mind, and lots and lots of money? Again, it’s both exhilarating and terrifying. Would you like an example?
Then allow me a few moments to tell you the story of Max Hodak, who as a child, learned how to develop film the old-fashioned way in a darkroom with his now deceased grandfather who was nearly blind.
According to a report published on MSN:
Hodak’s grandfather had retinitis pigmentosa, a congenital disease that affects one out of every 5,000 people — more than 2 million worldwide. Most people with the condition are born with their sight intact. Over time they lose peripheral vision first, then central vision, and finally, their sight, sometimes as early as middle age.
“He clearly had this career and was a photographer, and I saw that,” Hodak said of his grandfather, who became an aerospace engineer and briefly worked on heat shields for spacecraft. “But most of my memories as a kid was that he was pretty profoundly blind.”
Possible solutions, though, are within reach. Science, a start-up company in Alameda, Calif., has designed a visual prosthesis called the Science Eye which could restore vision, albeit in a limited form, in people with retinitis pigmentosa. Hodak, its CEO, co-founded the startup after a stint at Elon Musk’s company Neuralink. Other companies such as Paris-based biotechnology company GenSight Biologics and Bionic Sight in New York are also experimenting with methods to restore sight.
All of these companies have built their work on a research tool in the field of neuroscience known as optogenetics, which is a type of gene therapy that takes proteins known as opsins directly into the eye through an injection. The purpose of the injection is to help boost the light sensitivity of cells that are located in the retina, which is a layer of tissue that is located at the rear of the eyeball.
Anand Swaroop, a senior investigator for the National Eye Institute in Bethesda, Maryland, says this procedure has a whole lot of promise, but there’s still quite a bit of room for improvement.
“At least at this stage, it seems to be very good in cases where someone is completely blind,” Swaroop went on to say of the experimental treatment. “You should be able to find your way around. You’re not going to bump into things, which is great. But you’re not going to be distinguishing many different features.”
So how does all of this work?
In normal vision, light enters the eye through the lens and forms an image on the retina. The retina itself is composed of several different types of cells, mainly photoreceptors. Photoreceptors are light-sensing cells shaped like rods and cones that contain opsins. Normally, photoreceptors convert light into electrical signals that travel to the retina’s ganglion cells, which in turn transmit those electrical signals via the optic nerve into the brain. That’s how you’re reading the words on this page right now.
In retinitis pigmentosa, the rods and cones in the photoreceptors break down and ultimately die. First the peripheral vision goes, and people develop tunnel vision: They have to turn their whole head just to view the world around them. Many people with tunnel vision require a cane to assist in navigating the world (and to avoid bumping into things, like furniture.) Blindness follows not long after. The breakdown of the photoreceptors, however, doesn’t diminish the brain’s ability to process electrical signals — and, critically, the ganglion cells remain intact.
The process of optogenetics tries to get around the typical choreography by taking the opsin proteins straight into the ganglion cells, which enables them to be stimulated by light so they will send signals up to the brain.
There are two elements in the Science Eye. The first one is an implant that is made of a wireless power coil and features a super thin, highly flexible micro-LED array that is placed over the retina. Hodak revealed that this array — which is currently being tested on rabbits — gives eight times the resolution of an iPhone screen.
The second piece is a pair of frameless glasses, which are of similar shape and size to prescription glasses, that contain super tiny infrared cameras and inductive power coils. Ultimately, after the procedure is completed, the eye is no longer receiving an image, but digital information instead.
“You should be able to walk across town to buy a sandwich without being hit by a car,” Hodak remarked.
Clinical trials should begin, Hodak said, sometime in the next 18 months. The company is also looking at ways to use Science Eye to help people with dry age-related macular degeneration, which unfolds slightly differently compared with retinitis pigmentosa: Patients lose central, high-resolution vision first, and then their peripheral vision.
There are milestones to cross for every company using optogenetics to help people improve their eyesight. More patients enrolled in clinical trials should help refine both opsin delivery and the ability to improve light sensitivity in retinal cells. But Hodak predicts that over the next five years, there will be products on the market for people like his grandfather.
“You always have to be really careful with what you say to patients because they’re holding on for any piece of hope,” Hodak commented. “But there’s a lot of things on the horizon that are converging. It’s not at a point where any one thing will fail and derail the whole field. Real progress is coming.”