But this week Mr Zderad was able to see again, thanks to a groundbreaking procedure performed by surgeons at the Mayo Clinic in Rochester, Minnesota.
Mr Zderad was fitted with a Second Sight implant, which bypasses the damaged retina and sends light-wave signals to the optic nerve. Mr Zderad also had an electronic chip embedded in his right eye, which works in conjuction with a prosthetic device set in a pair of special glasses.
The patient was soon able to make out shapes, human forms and his own reflection. When he saw his wife sitting in front of him, the pair burst into tears.
This is only the beginning. We live in amazing times.