Computed tomography evaluation of the inner ear as a diagnostic, counselling and management strategy in patients with congenital sensorineural hearing impairment

The value of computed tomography (CT) of the petrous bone in the investigation of congenital sensorineural hearing impairment has been questioned. We have conducted a study to establish the usefulness of CT of the temporal bone in the evaluation and management of a consecutive series of unselected adolescent patients with congenital sensorineural hearing impairment of greater than 50 dB HL. Seventy-one patients (142 ears) were identified and images reviewed to establish the incidence of inner ear malformations. Fifteen ears were found to be abnormal in eight patients (seven bilateral and one unilateral abnormality). Three patients had Mondini abnormalities and one of these also had dilatation of the lateral semicircular canals. There were five patients with dilatation of the vestibular aqueduct. One patient had a unilateral dysplasia of the middle and external ear. A variety of incidental intracranial abnormalities were also discovered. We conclude that CT does have a valuable role in the management of SNHI.