I'm John Betts with Mary Roach, the author, and her new book is Replaceable You.

It's futuristic.

It's also at the same time heartening for those who've had surgery and concern themselves with their appearance afterwards.

We come now to donors, that is, the widow and the children of a deceased coal miner, for example,

or any gentleman or mother who's gone.

What do you need to know about what the needs are and what happens?

Let's start with the eyes, Mary.

They need eyes from cadavers. You can

actually replace a human eye with a human eye of a deceased person. Is that correct?

The cornea. I see. No, no one is transplanting the entire eyes. And the eye, the optic nerve is it's really part of the brain

so it's it would be a that's that's a tricky one to replace but the cornea which is the very

very thin layer on the exterior of the eye which can be removed and can be transplanted.

There are certain diseases.

Fuchs dystrophy is one of them where a corneal transplant is the most common treatment for

that.

So, and it's a, it's a tremendous gift.

And there's a big need because, you know, they don't always take sometimes

several efforts are needed before one takes.

They're getting much better at it at taking a thinner and thinner layer of the cornea.

It is a very thin.

I pictured a cornea as kind of like a contact lens, but it's

much thinner. So that's one thing. When somebody is a tissue donor, there's a great variety

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