Vision problems affect a huge part of the world's population, manifesting in a range from mild image blurring to complete blindness. Although prescription glasses and contact lenses are standard solutions, many seek a more permanent alternative. This is precisely why hundreds of thousands of people each year opt for corrective eye surgery, with the LASIK method being one of the most popular. This laser-assisted procedure, which reshapes the cornea and corrects vision, carries certain risks despite its high success rate. Motivated by this, scientists are developing a revolutionary technique that could completely eliminate the laser and cutting from the equation, offering cornea reshaping at a molecular level.

At the scientific meeting of the American Chemical Society (ACS), which is being held these days, results were presented that could forever change ophthalmology. Michael Hill, a professor of chemistry at Occidental College, presented his team's work on a new method based on electrochemical principles, and the first tests on animal tissue show extraordinary potential.

How does our vision work and why do errors occur?

To understand the importance of this discovery, it is crucial to know the basics of the human eye. The cornea, a transparent dome-shaped structure at the front of the eye, plays a crucial role in our vision. Its main task is to refract light rays coming from the environment and precisely direct (focus) them onto the retina, a layer of light-sensitive cells at the back of the eye. The retina converts these light signals into electrical impulses that it sends to the brain, where they are interpreted as the image we see. Any deviation from the ideal shape of the cornea leads to improper refraction of light, resulting in a blurry image. It is precisely these irregularities that cause the most common refractive errors such as nearsightedness (myopia), farsightedness (hyperopia), and astigmatism.

The dominance of LASIK: Precise cutting with potential consequences

For decades, LASIK (Laser-Assisted in Situ Keratomileusis) has been the gold standard in surgical vision correction. The procedure involves the use of two lasers: first, a femtosecond laser creates a thin, precise flap on the surface of the cornea. This flap is then lifted, and an excimer laser, guided by a computer, removes microscopic parts of the tissue beneath it, changing the curvature of the cornea to correct the refractive error. Afterward, the flap is returned to its place where it adheres naturally without the need for stitches.

Although LASIK is considered an extremely safe and effective procedure, it is not without its drawbacks. The very act of cutting tissue, although laser-precise, irreversibly damages the structural integrity of the eye. Potential side effects include dry eye syndrome, problems with night vision such as glare or halos around light sources, and in very rare cases, more serious complications related to the flap. As Professor Hill points out, "LASIK is really just a fancy way of doing old-fashioned surgery. You're still carving tissue—you're just using a laser instead of a scalpel." The question arises: what if we could achieve the same, or even better, result without a single cut?

A revolution on the horizon: Electromechanical Reshaping (EMR)

The answer to that question lies in an innovative approach called electromechanical reshaping (EMR). This method, as often happens in science, was discovered almost by accident by Dr. Brian Wong, a professor and surgeon at the University of California, Irvine, and Hill's collaborator on the project. "I was looking at living tissues as materials that you can engineer, and that’s how I came across this whole process of chemical modification," explains Wong.

The basis of EMR lies in the fundamental structure of collagenous tissues, to which the cornea belongs. The shape and strength of these tissues are maintained thanks to a complex network of collagen fibers and electrostatic attractions between oppositely charged molecular components. Since these tissues are rich in water, applying a mild electrical potential to their surface can cause a local change in pH, making the tissue more acidic. This change in acidity temporarily "releases" the rigid bonds within the tissue, making it pliable and susceptible to shaping. When the electrical potential is turned off and the pH value returns to normal, the tissue "locks" into its new, desired shape.

Before focusing on the eye, the researchers successfully applied EMR to reshape cartilage in rabbit ears and to change the structure of scars and skin in pigs, proving the versatility and effectiveness of this technology.

[Image of the human cornea structure]

First experiments on the cornea: Promising results without a scalpel

In the latest research, the scientific team applied this technique to isolated rabbit eyeballs. They constructed specialized "contact lenses" made of platinum, which served as a mold for the corrected shape of the cornea. Each lens was placed over an eyeball immersed in a saline solution, which simulates the natural environment of tears. The platinum lens also served as an electrode.

By applying a small electrical potential to the lens, the researchers generated a precise change in pH in the cornea. In just about sixty seconds, the curvature of the cornea adapted to the shape of the lens. The entire process takes about as long as LASIK, but requires significantly fewer steps, uses cheaper equipment, and most importantly, involves no cuts. The procedure was repeated on 12 separate eyeballs, 10 of which were treated as if they had nearsightedness. In all 10 "nearsighted" cases, the treatment successfully achieved the targeted change in the eye's focusing power, which in a living organism would correspond to a significant improvement in vision.

More than vision correction: Potential for treating diseases

Analyses showed that the cells in the cornea survived the treatment without damage, thanks to a carefully controlled pH gradient. But the potential of this technology extends beyond mere diopter correction. In other experiments, the team demonstrated that their technique might be able to reverse certain forms of corneal clouding caused by chemicals. This is a condition that can currently only be treated with a full corneal transplant, a complex surgical procedure that carries the risk of tissue rejection.

The path to clinical application: Challenges and the future

Despite the extremely promising initial results, the researchers emphasize that the work is still in a very early stage. The next step, as Wong describes it, is "the long march through careful and precise animal studies," which includes testing on live rabbits, not just their isolated eyeballs. They also plan to determine the full scope of EMR's capabilities, i.e., whether the technique can be used to correct all types of refractive errors, including farsightedness and astigmatism.

Although the next steps are clearly defined, the future of the project is uncertain due to difficulties in securing funding for further research. "It’s a long way from what we’ve done to being in a clinic. But if we can get there, the technique has the potential for broad application, it would be a lot cheaper, and it might even be reversible," concludes Hill, leaving hope that we might soon witness a new era in eye health care.