Eyeballs give me the willies, even when they are in the head.
I forget where I read this, but during WWII both of a serviceman's eyeballs were popped out of his skull by a bomb blast. He was alive but his eyes were hanging on his cheeks by the optic nerves. A fellow military man who encountered him just pushed the eyeballs back into the sockets and the guy was good to go. His eyes were functional again. I'm ashamed to admit that were I to come upon such a poor soul my squeamishness would prevent me from helping.