Cross section of rabbit cornea successfully flattened by an electromechanical reshaping technique, from its original shape white line to a corrected one yellow line. Credit Daniel Kim and Mimi Chen

US researchers have presented trial results showing electromechanical reshaping (EMR) was effective in flattening rabbit corneas, which they said could offer an alternative to LASIK in humans.

Professor Brian Wong, a head and neck surgeon at the University of California, and Michael Hill, professor of chemistry at Occidental College, Los Angeles, presented their results at the recent meeting of the American Chemical Society. They found applying an electric potential to the cornea lowers the tissue’s pH, loosening fixed negative charges in the collagen matrix and making the shape malleable. When the original pH is restored, the tissue is locked into the new shape, they explained.

The team constructed platinum ‘contact lenses’ as a template for the corrected corneal topography, then placed each over a rabbit eyeball in artificial tears. The lens acted as an electrode to generate a precise pH change. After about a minute (around the same time LASIK takes) the cornea’s curvature conformed to the shape of the lens.

The whole effect was discovered by accident, said Professor Wong. “I was looking at living tissues as mouldable materials and discovered this whole process of chemical modification.” The team had previously used EMR to reshape cartilage-rich rabbit ears, as well as to alter scars and skin in pigs.

The team said it also demonstrated the technique could reverse some chemical-caused corneal cloudiness, which is currently only treatable through a complete corneal transplant.

EMR’s advantage over LASIK is it doesn’t compromise the corneal tissue, said Prof Hill. “LASIK is… still carving tissue – it’s just carving with a laser.” With the procedure not yet tested on a living rabbit, only its eyeball, there’s a long road to EMR being used in the clinic instead of LASIK, he said. “But, if we get there, this technique is widely applicable, vastly cheaper and potentially even reversible.”

Watch the procedure on YouTube