External Auditory Canal Fracture

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Fall on mandible with blood from both external auditory canals. CT shows bilateral comminute fracture of the bony parts of external auditory canals (arrows). Fractures are not apparent at first glance, however clue here is emphysema - air in soft tissues medially to mandibular condyles (arrow heads). Mechanism of this trauma is impact of mandibular condyles against anterior parts of the bony external auditory canals. Lesson here is to look carefully at any abnormal air in soft tissues of trauma patients and ask yourself a question: Where does this air come from?

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