Mastoid volume and eustachian tube function in ears with cholesteatoma.

Eustachian tube function, as measured by the pressure equalizing technique, and the mastoid air cell area were compared among ears with traumatic eardrum perforations, ears with chronic otitis media, and cholesteatomatous ears. A statistically significant difference among the three groups was found regarding the residual positive pressure after swallowing, with the poorest function found in the cholesteatoma group. Also, the ability to reduce a negative pressure was found to be inferior in the cholesteatoma group compared with the others. The mean mastoid air cell area measured on the x-ray film was smallest among ears with cholesteatoma and differed significantly among the groups. These disturbances in the active eustachian tube function as well as the volume of the middle ear cleft, including the mastoid air cell system, were found to be characteristic among ears with acquired cholesteatomas.