A clinico-radiological study of the contralateral ear in acquired unilateral cholesteatoma

Clinico-audiological and CT scan assessments of the contralateral ear in patients with unilateral cholesteatoma can be a good predictive method for the fate of these ears.

Fifty patients with unilateral cholesteatoma and 25 control subjects with bilateral normal ears were subjected to otomicroscopical and audiological assessment. Axial and coronal computed tomography (CT) for the mastoid bone at 1 mm slice thickness was done for all ears. A simplified method was used to find out the surface area (SA) of the air cells at each individual section and semi-automatically calculate the total volume of the matstoid air cells.

Otomicroscopically, 72% of the contralateral ears showed signs of retraction pockets, granulation tissues and other signs of chronicity. Audiologically 20% of the control ears showed moderate to severe conductive hearing loss while 10% showed mixed hearing loss. As regards mastoid pneumatization, the mean air cell volumes were 6.1, 12.68 and 29.92 CC in cholesteatomatous, contralateral and control ears respectively. This indicates a highly significant difference in the mean air cell volume between the control ears and the other two groups.

It can be concluded that continuous follow up of the contralateral ear in cholesteatomatous ears is mandatory to detect subtle pathological changes and manage them early. Volumetry of contralateral ear using the applied simple method can lead to a reduction in major surgery and can affect the choice of the surgical approach.