venerdì 28 aprile 2006
There is osseous obliteration of the visualized cochlea (Figure 1), vestibule, and lateral semi-circular canal (Figure 2).
Diagnosis: Labyrinthitis ossificans
The most common causative factor is inflammation of the inner ear, secondary to bacterial meningitis and subsequent purulent labyrinthitis. Other, less common causes include labyrinthectomy, temporal bone trauma, autoimmune inner ear disease, sequela of mumps or measles, and otitis media with associated suppurative labyrinthitis.
Ossification in labyrinthitis ossificans commonly occurs primarily at the basal turn of the cochlea, which is the insertion site of the electrodes of cochlear implant devices, and subsequently may interfere with full insertion and successful results. MRI is used to assess for early fibrosis prior to the formation of calcification.