All patients in the Birmingham Cochlear Implant Programme underwent computerized tomography (CT) scanning and were assessed and images interpreted by the main author. Of the first 100 cases, 20 were considered to have abnormalities of the inner ears by CT imaging. It is concluded that the commonest abnormality was cochlear otospongiosis followed by labyrinthitis ossificans.
Otospongiosis is well shown by CT which gives a good predicator of luminal patency.
However, labyrinthus obliterans, although usually apparent on CT, is not reliably shown in all cases and T2 weighted magnetic resonance imaging (MRI) is better.