Who is the oldest deaf and blind woman to graduate from college?

Years ago I read a wonderful book about a woman who was both deaf and blind. (Not Helen Keller) She was in her 80's when she graduated college. She was found in a mental institution and rescued from it. No one there realized that she was deaf and blind and otherwise healthy. I want to recommend it to a friend but I can't remember her name or the author's name. Thank you!