Head and Neck ImagingKeratosis obturans
epidermal keratin plug in the external auditory canal, often bilateral. The presenting symptoms are pain and
conductive hearing loss. This condition is seen in young patients, typically with a history of
sinusitis or bronchiectasis. On
CT, soft tissue thickening and expansion of the external auditory canal is seen, together with bony erosions. The differential diagnosis is external auditory canal
cholesteatoma, which is usually a unilateral disease, showing on
CT a localized erosion of the canal wall.
RH