Incidental Tracheocele as an Unusual Presentation of Pneumomediastinum in the Trauma Setting.

BACKGROUND Tracheocele are rarely encountered air cysts formed due to tracheal wall outpouching through a weak vantage point. The majority are acquired in the adult population and are associated with conditions that weaken the tracheal wall. Most tracheoceles are diagnosed incidentally since many are asymptomatic or present with nonspecific symptoms.