Almost 2.2 billion people suffer from some form of vision impairment— that’s almost 1 in every 4 person worldwide. Nearly half of these cases could have been prevented or are unaddressed. While LASIK remains the gold standard, helping patients achieve 20/20 vision in over 90% of the cases, it has a few drawbacks. The procedure itself is minimally invasive, requiring no incisions or stitches, but it still carves tissue. LASIK can cause dry eyes, halos, glare, and weaken the corneal structure. The alternative discovered by “accident” can simply reshape the cornea and correct vision with no need for lasers or invasive surgery.
Researchers from Occidental College and the University of California, Irvine have been developing an experimental technique called electromechanical reshaping (EMR) which temporarily softens the cornea so that it can be molded into a new shape. Early tests in rabbit eyes have been quite successful, and scientists hope to use this technology to correct vision in a way that is cheaper and safer than LASIK.
An Accidental Discovery
The idea behind EMR was not originally planned to reshape the cornea to correct vision, but to study living tissues as moldable materials. Brian Wong, a professor and surgeon at the University of California, Irvine, claims to have accidentally discovered the chemical modification of the cornea.
Collagen-rich tissues are present throughout the body, from cartilage to the walls of blood vessels. The cornea, too, is rich in collagen, and its shape is maintained by a meshwork of charged molecules holding the structure together. The tissue also contains a good amount of water, so applying a mild electric current can temporarily alter its acidity (pH).
As the pH shifts, the molecular bonds that hold the tissue rigid begin to loosen, making the cornea pliable. Once the shape is altered, the current is withdrawn as the pH returns to normal, at which point the cornea stiffens again and locks into its new form.
Platinum and Electricity Mold the Cornea
To test the method, the team created specialized platinum “contact lenses” shaped to match the cornea’s desired curvature. Rabbit eyeballs were placed in a saline solution that was designed to mimic natural tears, while the platinum lens served as an electrode. Upon applying a small current, the cornea gradually softened and conformed to the shape of the lens. The entire process took about a minute, similar to the time required for LASIK, but without the need for expensive lasers or tissue removal.
The team tested the procedure on 12 rabbit eyeballs, 10 of which were treated to correct nearsightedness (myopia). The treatment successfully corrected vision by molding the cornea to the intended focusing power, thereby improving vision. Interestingly, the cells within the tissue remained alive because the researchers fine-tuned the pH changes during treatment. In separate experiments, the same technique showed promise in reversing certain forms of chemical cloudiness in the cornea. As of now, chemical cloudiness requires a full corneal transplant.
Safer, Better, and Cheaper
Scientists believe that removing corneal tissue with LASIK can weaken the cornea’s structure, which is preserved in EMR. Laboratory imaging studies and microscopy suggested that the cornea’s collagen structure remained largely intact after treatment. Researchers also reported no obvious tissue damage or loss of transparency in the early experiments.
More recent reports and engineering tweaks have continued to polish the technology. Scientists are now working to develop advanced electrode contact lenses that can monitor corneal shape, hydration, and transparency during treatment. Although EMR has been tested for nearsightedness, research is underway to determine whether it is adaptable for farsightedness and astigmatism, as well as for reconstructive procedures involving collagen-rich tissues.
Light at the End of a Long Tunnel
Despite being elated, scientists caution that EMR remains highly experimental. So far, the technique has been tested on isolated rabbit eyes rather than on living animals, or on humans, as in a clinical trial. The next phase involves extensive animal studies to determine how stable the reshaped cornea remains over time, and if the procedure is safe in living tissue.
“There’s a long road between what we’ve done and the clinic,” concludes Michael Hill, a chemistry professor at Occidental College. “But, if we get there, this technique is widely applicable, vastly cheaper and potentially even reversible.”
For the time being, LASIK will be the standard option for surgical vision correction. EMR has opened the door to a future in which non-invasive techniques can help correct vision at a lower cost than LASIK, with greater safety.
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