One of my most interesting cases occurred several years ago. A patient was referred to my office after brain surgery. Her complaint was that she would continuously walk into walls. Her eyesight was clear as she was 20/20 in each eye. Her problem was with her peripheral vision. She was missing the right side of her vision, probably as a result of the surgery. Even though I cannot restore a lost visual field, I was able to shift the lost vision over to the side with prisms. This made the patient more balanced in her visual world. She was able to perform a lot better. To start with, she wasn't walking into walls anymore. Secondly, her outlook toward life improved immeasurably as a result. Also, she was able to read a lot better. The result was immediate.