The appearance of a few pathologies Atresia of the external auditory meatus is a predictable, but rare inherited abnormality. Destruction of the scutum is an indicator of Cholesteatoma , a complication of chronic otitis media Otosclerosis is an acquired condition. It may be generalised and classically presents as perilabyrinthine otosclerosis, but may be more localised. More correctly the condition perhaps should be called a peri-labyrinthitis or spongiosis. It is characterised by a thickened, increased bone density and fixity of the stapes with resulting deafness.
Accoustic neuromas can expand the internal auditory meatus and fill the cerebello-pontine angle.
Subtle pathology may be missed. The technique involved lumbar puncture and the trickling of a small amount of air up the theca to the sub-arachnoid space in the posterior fossa. The head was tilted to allow the air to rise into the internal auditory meatus. The presence of air in the internal auditory meatus outlines vessels and nerves, revealing the neuroma in this instance.