Improvement in bone conduction threshold after tympanoplasty.

Abstract

To investigate the causes of bone conduction threshold impairment associated with middle ear pathoses and the factors influencing improvement in bone conduction threshold after tympanoplasty. The records of 98 consecutive patients with unilateral chronic otitis media who underwent tympanoplasty were reviewed. Pre-operatively, 15 dB or more depression of bone conduction threshold at least in 2 frequencies between 500 and 6000 Hz was considered to be significant. Similarly in the postoperative period, 15 dB or more improvement of bone conduction threshold at least in 2 frequencies between 500 and 6000 Hz was regarded as significant. Twelve (12.5%) of 98 cases were found to have depressed bone conduction threshold; 6 of 12 cases had improved bone conduction threshold after tympanoplasty. In cases with cholesteatoma and extensive middle ear disease, successful results could be achieved after tympanoplasty disregarding the air-bone gap and deteriorated bone conduction threshold. Bone conduction threshold may improve after tympanoplasty.