A new, promising technique has the potential to replace laser surgeries in ophthalmologists’ offices in the future, for a fraction of the cost. Called electromechanical reshaping (EMR), the technique offers a gentler approach to correcting the cornea than Laser-Assisted in Situ Keratomileusis (LASIK), today’s gold standard for treating vision issues including nearsightedness, farsightedness, and astigmatism.
The eye develops these and other conditions when the cornea’s curvature is off—too steep, too flat, or too uneven. To solve the problem, surgeons generally use laser techniques such as LASIK to “sculpt” the eye surface by cutting away small parts of corneal tissue. The results can be life-changing, but the procedure has its risks, as LASIK permanently reduces corneal strength, raising the risk of new vision problems.
Alternative nonsurgical methods such as specially designed contact lenses can temporarily mold the cornea, but these require nightly wear and can cause infection. Now, engineers and eye doctors are trying to find a way to permanently reshape collagen-rich tissues like the cornea without cutting, burning, or removing material.
Brian Wong, a surgeon-engineer at the University of California, Irvine, stumbled upon a possible solution about a decade ago. He had long worked with thermal techniques for reshaping cartilage tissues—which include the cornea—but found a puzzling “Goldilocks problem” during his research: The heating needed to change shapes often killed too many tissue cells. Then a “happy accident” opened a different perspective, he says. “My postdoctoral fellow connected a pair of electrodes and a Coke can to a power supply…and out of spite, fried a piece of cartilage,” Wong recalls. The cartilage began to bubble, which the postdoc thought was from heat. “But it wasn’t hot. We touched it and thought, this is getting a shape change. This must be electrolysis,” he says.
That surprise pointed to electrochemistry rather than heat as the mechanism. To explore further, Wong partnered with Michael Hill, a chemist at Occidental College. Together, they began exploring the chemistry behind EMR and testing it in different tissues. In mid-August, they presented results from their most recent tests at the American Chemical Society’s fall meeting that took place in Washington, D.C.
How Electricity Reshapes Tissue
EMR uses small electrical pulses to split water at the tissue surface into hydrogen and oxygen, releasing protons that spread into the part of the corneal tissue that gives it structural integrity, the ability to hydrate, and other mechanical properties.
Once protons are spread throughout the cornea’s surface, they disrupt the chemical bonds that hold collagen fibers in place, also changing the corneal tissue’s pH. This, Wong explains, is the moment when the cornea becomes moldable. Once shaped with a metal contact lens–like mold, it “locks in” to the new shape as the electric pulses are turned off and the body’s natural physiological response returns the cornea’s pH back to its normal value.
In 2023, Wong and Hill coauthored a proof-of-concept paper in ACS Biomaterials Science & Engineering, showing that EMR could reshape rabbit corneas without compromising transparency. “That paper was really about asking, is it even possible? Can we change the shape of a cornea without gross damage?” Hill says. “Now, after two more years of work, we’ve systematically gone through the parameters—and we can say yes, it is possible, and we can do it safely,” he adds.
Their team built custom platinum contact lenses, press-molded to precise curvatures, and connected them to electrodes. Mounted onto rabbit eyes immersed in a saline solution, the electrodes delivered pulses of around 1.5 volts. X-ray imaging tests confirmed the corneas had indeed matched the mold’s shape. Microscopy tests also confirmed the collagen tissue remained organized post-surgery. “Fine control is the key,” Wong observes.
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