Corneas made in the lab using genetically engineered human collagen could restore sight to millions of visually impaired people waiting for transplants from human donors, researchers say.

In a newly released study, investigators from Canada and Sweden reported results from the first 10 people in the world treated with the biosynthetic corneas.

Two years after having the corneas implanted, six of the 10 patients had improved vision. Nine of the 10 experienced cell and nerve regeneration, meaning that corneal cells and nerves grew into the implant.

‘This is the first time we have been able to regenerate a cornea in humans,