I went to have my eyes checked about 6 months after surgery and was ask "Any recent surgeries?" My doctor noticed my response said "If there is not improvement in this exam and there should be you will see improvement even continual for the next year to two years." I ask if this was common parathyroid disease, she said that every single patient that she had seen this was true with and that too much calcium in the blood can make you blind. I did have a significant improvement.