Hi Santhiya
Corneal graft rejection is a condition that can occur if your body's immune system recognizes the graft as 'foreign' and then starts attacking it.
Nowadays, there are several kinds of corneal transplant operations that can be performed for keratoconus.
Usually, we try to perform 'deep anterior lamellar keratoplasty' (DALK) where the abnormal collagenous stroma is replaced but your own inner corneal lining (endothelium) is preserved. Sometimes, the entire thickness of cornea may need to be replaced in a procedure called 'penetrating keratoplasty' (PK).
If you had DALK, the rejection is often reversible as it does not affect the corneal endothelium. If you had PK and endothelial rejection, the cornea may still be cleared sometimes if the rejection was detected and treated early enough.
However, sometimes when the endothelium is damaged beyond a certain level, the cornea may remain hazy because the damaged endothelium cannot regenerate. Further surgery may even be necessary sometimes-it all depends.
As you can see, the possibility of restoring your vision and the options for achieving that depend on a number of things, some of which we will only know after a full assessment with other instruments during a full clinic consult.
I would suggest that if you would like a second opinion, that you arrange an appointment with a corneal specialist so that the necessary information can be obtained to advise you further.