Axial high resolution bone window images of bilateral temporal bones:
Right temporal bone
- ossification of membranous labyrinth involving all the cochlear turns (complete obliteration of middle and apical turns)
- non-visualisation of all the semicircular canals, indicating complete obliteration of the canals by the ossification. Vestibule is spared
- features of chronic otomastoiditis are noted in the form of non-visualised middle ear ossicles, soft tissue opacification of mastoid antrum, retracted tympanic membrane with focal perforation of the posterior aspect of pars flaccida of tympanic membrane
- cochlear and vestibular aqueducts are well seen
These features are suggestive of labyrinthitis ossificans.
Left temporal bone
- fluid opacification of mastoid antrum and epitympanic recess of middle ear cavity with normal appearance of middle ear ossicles, representing chronic oto-mastoiditis
- membranous labyrinth appears normal
- retraction of tympanic membrane is noted