ot: Well ... that shows how much I know (not much). I thought it was the nerves or maybe muscles that were donated. Maybe even a healthy retina can be transplanted.
I've heard that the eyeball doesn't grow in size after birth ... it's for that reason babies seem to have such large eyes, because they're full size.
I wonder if a transplant of the entire eyeball, with all nerves and muscles still attached, is possible yet. If not, it will be eventually, I imagine.
Fascinating stuff.