Yes, it is possible for you cure the blindness by cornea transplant if your blindness reason is related with corneal problems. Usually the surgery of cornea transplant is safe and effective in the formal hospital. Before the surgery, you will have to accept the test to see whether you are qualified to do the surgery. Thus it is safe and effective.
Well, generally speaking, it can not cure blindness. First, you should know what the cornea transplant is. In common, the cornea is the tissue on the very front of the eye. And cornea is clear and covers the iris and pupil. When the cornea becomes swollen, or scarred, you may need the corneal transparent to treat it. With the surgery, it will just solve the problems, but on the other hand, it will also increase some risks. For example, it may lead to eye infection, because you do not protect your eyes from virus carefully. And when the recovery is infected by some other eye diseases, it can just affect your corneal, leading to eye infection. but in common, it can be safe.
All right, it is true that corneal transplant could help with the risk of being blind because it replaces our impaired or infected cornea, it could greatly improve our vision and even regain our vision if we are blind. Anyway, it is quite safe if the hospital provide reliable treatment and surgery service. Just try to get the right treatment.