ABSTRACT
This chapter reviews the appropriate imaging in a range of clinical scenarios. Cone beam computed tomography (CBCT) is emerging as a ‘low-dose’ alternative to standard CT in certain clinical settings. The high spatial resolution of CT is optimal for demonstration of the cortical bone and air spaces of the middle ear whereas the superior contrast resolution of magnetic resonance imaging (MRI) is ideal for imaging the inner ears, petrous apex and intracranial structures. There are wide variations in the use of imaging in this clinical setting. Necrotising otitis externa should be imaged for diagnosis and to demonstrate its extent. While CT may demonstrate the early changes of tympanic bone erosion, MRI with gadolinium better shows the involvement of the subcranial soft tissues and the central skull base. CT will be indicated in the setting of conductive hearing loss when there is associated chronic suppurative otitis media, congenital aural dysplasia, trauma or an otoscopically visible mass.
