You would probably also need glasses if you got both eyes and part of your brain gouged out, not that it would help you alot xD
It does seem a little bit strange though. Maybe Haise had bad vision but was so used to it he didn't notice, but then Kaneki came back and was all; "wtf is this? I can't see shit!"
Sorry, i can't handle this manga unless i make jokes about it on a regular basis
You are unique, just like everybody else.