Recurrent meningitis in an adult secondary to an inner ear malformation: imaging demonstration.

Congenital labyrinthine dysplasia with a translabyrinthine cerebrospinal fluid (CSF) fistula may be an anatomic cause for recurrent meningitis. This condition is usually seen in children aged 5 to 10 years who present with sensorineural hearing loss (SNHL) and CSF discharge through the nose or ear, with or without recurrent meningitis. Multidetector-row computed tomography (MDCT) and high-resolution T2-weighted magnetic resonance imaging (MRI) of the petrous portion of the temporal bone can help to diagnose this abnormality. We report a case of translabyrinthine CSF fistula in an adult-a 30-year-old man-who presented with recurrent pneumococcal meningitis, a long history of a clear nasal discharge, and evidence of SNHL. MDCT and MRI of the temporal bone demonstrated a cystic-appearing cochleovestibular malformation (an incomplete partition type I) in the right inner ear. Imaging also showed an absence of the basal turn of the cochlea and the cribriform membrane at the lateral end of the right internal auditory canal, which was shorter and narrower than normal. Evidence of fluid in the right middle ear suggested a CSF fistula.