What is it?
This patient has a full-thickness cut in the sclera from a sharp instrument. Similar lacerations can result from blunt trauma. They may be very hard to locate, especially if they are hidden behind a bloody, swollen conjunctiva. Indirect evidence of a scleral laceration is a deformed or low pressure globe.
What to do?
Look for scleral lacerations, but don't expect to find them because they may be hidden. Presume that the globe is ruptured if it is deformed or if there is massive conjunctival ecchymosis.
Do not try to pry apart the eyelids if you suspect a ruptured globe! Place a shield over the orbit and call an ophthalmologist.