Surgery question?

Question

Are eye transplants possible? If not then what prevents this surgery from being sucessful?

Answer 1

With our current technology it is not now possible to transplant an entire eye. It is very common, though, to transplant corneas. In fact it is a highly succesful procedure with a quite low recipient rejection rate. The cornea gets its oxygen from the surrounding air. Therefore, it has no blood vessels. Because it has no blood vessels it is much less likely to be rejected by the recipient because most antibodies which can cause rejection are carried in the blood.

The two problems that must be overcome with a total eye transplant are 1) recipient rejection and 2) regeneration of the optic nerve. Recipient rejection is really no more a problem than any other transplant performed such as kidney or heart. The same medications to control rejection could be used. The BIG problem is that the optic nerve is a CNS nerve. Central Nervous System. Peripheral nerves such as you find in the arm or leg can over time regenerate and grow to again function to send and receive signals from the organ peripheral to where the nerve is severed. BUT, central nervous system nerves respond quite differently when they are severed. For example look at Christopher Reeves (Superman). He severely damaged and severed CNS nerves in his neck. Even though it appears he may have regained a small amount of innvervation, for all intents and purposes his injury did not improve and the damaged CNS nerves were not capable of regenerating. He remained an invalid the remainder of his life.

To transplant an entire eye one would have to sever the optic nerve and then reattach it through microsurgery to the new donor transplanted nerve attached to the donor eye. Until we can figure out how to effectively stimulate a CNS nerve to regenerate all we would be able to accomplish is to put a new eye in the recipient's socket but the recipient's brain would not be able to receive any information from the transplanted eye. Doesn't make much sense to do this when prosthetic eyes are so realistic now and there is no risk of complication of rejection of a prosthetic eye. Hope this helped.

Answer 2

No, whole eye transplants are not possible. The optic nerve will not regenerate and heal to allow images to be sent from the retina to the brain.