Perilymphatic fistula and pneumolabyrinth without temporal bone fracture: a rare entity

Post-traumatic pneumolabyrinth is an uncommon clinical entity, particularly in the absence of temporal bone fracture. We report the case of a patient who presented to our emergency department with a headache, sudden left hearing loss and severe dizziness which began after a traumatic brain injury 3 days earlier. On examination, the patient presented signs of left vestibulopathy, left sensorineural hearing loss and positive fistula test, normal otoscopy and without focal neurological signs. The audiometry confirmed profound left sensorineural hearing loss. Cranial CT revealed a right occipital bone fracture and left frontal subdural haematoma, without signs of temporal bone fracture. Temporal bone high-resolution CT scan revealed left pneumolabyrinth affecting the vestibule and cochlea. Exploratory tympanotomy revealed perilymphatic fistula at the location of the round window. The sealing of defect was performed using lobule fat and fibrin glue. He presented complete resolution of the vestibular complaints, though the hearing thresholds remained stable.