[Isolated apical petrositis: an atypical case of Gradenigo's syndrome].

In 1904 Guiseppe Gradenigo described an infection of the apex of the petrous part of the temporal bone from acute otitis media with the clinical symptoms of unilateral pain around the eye, diplopia due to sixth nerve paralysis and persistant otorrhea. While this infection became evident by inward extension from petrositis in the majority of fatal cases from acute otitis media in the preantibiotic era, it has now become very rare. Today, cases mainly derive from cholesteatomas or chronic osteomyelitis of the petrous bone. However, due to intense antibiotic treatment in acute otitis media clinical signs of petrositis may be less typical compared to former times. We report on a 12-year-old boy with rapid onset of sixth nerve paralysis without clinical signs of acute otitis media or mastoiditis. CT and NMR imaging confirmed infection of the petrous apex. He was treated by mastoidectomy with exploration of a posterior cell group from the epitympanon around the semicircular canals and subsequent high dose intravenous antibiotics. The patient recovered without any loss of inner ear or facial nerve function. The paralysis of the sixth nerve disappeared completely within 6 weeks.