Impedance Results after Myringoplasty

Abstract

Clinical examination, audiometry and impedance measurements were performed on 82 patients after myringoplasty. In the operated ears the mean compliance was 0.41 ml (S.D. 0.31 ml) and the middle ear pressure –8.1 mm H₂O (S.D. 34.2 mm H₂O). The respective values of 73 normal ears were 0.53 ml (S.D. 0.26 ml) and 0.0 mm H₂O (S.D. 19.4 mm H₂O). The tympanogram with 0.22 kHz probe tone was generally V-shaped, although in one case it was flat and in another W-shaped. In the normal ears the curve was always V-shaped. With 0.8 kHz probe tone a W-shaped curve was obtained in 31 of the myringoplasty ears but only in one normal ear. The stapedius reflex was positive in 31 operated ears and almost all of the normal ears. The correlations of tympanometry to both the clinical status and audiometry were good, but those of compliance values were low. Operated ears with a conductive gap often revealed a deep V-shaped curve with the 0.22 kHz probe tone and a W-shaped one with the 0.8 kHz probe tone.