[Otogenic extradural pneumatocele, 36 years after a gunshot injury].

In the reported case an extradural pneumatocele developed 36 years after the mastoid tip had been destroyed by a bullet. It had reached the occiput and led to destruction of the bone surrounding its distal end, so that air could be found directly under the galea. In the literature there are only few case reports referring the otogenic origin of a posttraumatic extradural pneumatocele. Furthermore, an overpressure in the middle ear cleft or mastoid could be excluded because of the presence of a tympanic membrane perforation. In spite of a chronically infected middle ear, there was no infection of the pneumatocele.