Researchers have been working with stem cells to replace damaged cornea tissue in patients. The stem cells come from their own eyes, so the patient must have at least some healthy tissue in one eye. Of course this technique wouldn't work for patients with damaged retinas or optic nerves, but it is still very promising.

Doctors have been performing this operation for a few years now and it sounds a lot like the procedure Mike May had, which is chronicled in the book Crashing Through: The Extraordinary True Story of the Man Who Dared to See (a great read, by the way).

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