Predictive value of ossicular discontinuity in chronic suppurative otitis media using pure-tone audiometry

OBJECTIVE To analyze the predictive value of preoperative air-bone gap(ABG)for ossicular discontinuity(OD)among chronic suppurative otitis media(CSOM)patients.METHODS Records of 56 patients with CSOM,who were 12 to 69 years old and underwent their first tympanoplasty,were reviewed.The pure tone audiometry was observed before operation.The presence or absence of OD was observed under microscope during operations.These patients were classified into two groups according to the presence or absence of OD.Frequency-specific ABG values and the mean ABG values of the 4 frequencies(0.5,1.0,2.0,4.0 kHz)were compared using T test between the two groups.RESULTS Compared with normal ossicular chain group,average ABG at speech frequencies(0.5,1.0,2.0,4.0 kHz)in OD group was higher,the difference was significant between the two groups(t=-4.043,P0.05).But frequency-specific ABG was higher only at 2 kHz among the 4 frequencies(t=-3.334,P0.05).CONCLUSION Preoperative ABG at 2 kHz frequence has predictive value for OD in CSOM.