>Test X-ray on the Rat
You don't want to boil your guts or anything, but you need to know what the surgeon dropped in your body. You feel a little guilty about it, but you test the machine on the creepy ear rat first, hoping that if it's safe for a rodent you found in a monster's laboratory, it might be safe for you.
The machine spits a printout onto the floor, and the rat shows no sign of sickness or pain. You put it back where you found it and step behind the machine yourself...