Head and Neck Imaging

inner ear, pathology

Congenital malformations
According to Jackler, inner ear malformations can be divided into a group with and a group without cochlear malformations. For those with cochlear malformations, see cochlea, pathology . Those with a normal cochlea are classified as:
- dysplasia of vestibule and semicircular canals
- enlarged vestibular aqueduct
However, recent detailed studies have revealed that patients with an enlarged vestibular aqueduct often have other inner ear malformations (see large vestibular aqueduct syndrome ).
Inflammation
The inner ear may be affected by several types of inflammation: viral or bacterial infection, and autoimmune disease. See labyrinthitis .
Otodystrophies
The otodystrophies that may affect the inner ear are: otosclerosis , Paget's disease , fibrous dysplasia, head and neck , osteopetrosis and osteogenesis imperfecta .
Tumour
Tumours may arise from within the membranous labyrinth (inner ear schwannoma). Intracanalicular acoustic schwannoma may extend into the inner ear along the cochlear nerve (see also hook shape sign, in acoustic schwannoma ). Tumours originating in the vicinity of the cochlea may encroach on its bony capsule.
Trauma
The inner ear may be involved in a transverse fracture, temporal bone . Hearing loss may be due to labyrinthine concussion, without a fracture visible on CT. Post-traumatic serous labyrintitis or inner ear haematoma may be revealed on MRI.

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