Artificial corneas are in sight

Scientists have tried to develop artificial corneas for half a century, but patients so far have not tolerated the prototypes well. A new biomimetic hydrogel or polymer developed by Stanford University researchers may change this. And it may help restore vision for millions of people blinded by damaged or diseased corneas. The material may also improve the view for millions more made near or farsighted due to misshapen corneas.

The transparent Duoptix material swells to a water content of 80% -- about the same as biological tissues. It's made of two interwoven networks of hydrogels. One network of polyethylene glycol molecules resists the accumulation of surface proteins and inflammation. The other comes from polyacrylic acid molecules that resemble materials used in super-absorbent diapers. The hydrogel is permeable to nutrients, including glucose, the cornea's favorite food. Its also strong and stretchy so it survives suturing during surgery.

Other ocular applications for the hydrogel could include more comfortable extended-wear contact lenses or those that could be implanted and then replaced if the prescription changes. Hydrogel lenses may even make their way deeper into the eye as replacements for inner-eye lenses damaged by cataracts.

Researchers have tested the material for biocompatibility in animals, reports Christopher Ta, an assistant professor of ophthalmology and ophthalmology at the Stanford University Medical Center. During eight-week trial, the material remained perfectly clear, he says.