My fish have scratched their eyes on the rocks before, kinda looks like pop eye but it's always just one eye that's effected so I know it was a physical injury. Very first time I saw it I caught the fish put it in QT treated it with med.'s and it died
Since then (it's happened to 3 of my other fish over the years, right now my powder blue tang has an eye scratch, but it's been a week and it's almost healed now) I leave the fish in the display and do nothing, it always heals on it's own in the display (without med.'s) within two weeks.