Corneal transplants are the oldest and most common organ transplants, but are unusual as we do not match the donor to the recipient. In other forms of transplant great care is taken in matching the donor to the recipient to reduce the chances of rejection. This is not helpful for corneal transplantation.
Corneal transplants, because they have no blood supply, are much less prone to rejection and there has not been any strong evidence to show that matching the blood type (or other immune markers) has any value in improving the outcome of corneal transplants.
Corneal transplants are performed in the operating theatre, under local anaesthetic usually, and they involve the removal of the existing cornea, or at least the central part of it, and replacement with a donor cornea. A donor cornea can now be stored for up to a month in a particular transport medium and donor corneas are now usually in good health and can bed in quite nicely to the recipient.
Corneal transplants require sutures to hold them in place and those sutures will often stay in place around twelve months from the operation.
It is rare to get substantially better vision within 6 months after a corneal transplant, although it does depend on how poor the vision is to start with. Often the visual recovery is quite prolonged so it is important to consider the recovery period in the surgical planning for a corneal graft.