术前听力学特征对镫骨固定的单纯性先天性中耳畸形的鉴别OA

OBJECTIVE To characterize the audiological features of isolated congenital middle ear anomalies.METHODS A retrospective analysis was conducted on baseline clinical data,preoperative high-resolution temporal bone computed tomography(HRCT),audiological examinations(including pure-tone audiometry),and intraoperative findings in 78 patients(93 ears)diagnosed with isolated congenital middle ear anomalies via tympanotomy.RESULTS The overall HRCT detection rate was 81.7％.Patients were categorized based on intraoperative confirmation of stapes footplate fixation status.The proportion of cases exhibiting a"Carhart notch"was significantly higher in the fixation group than in the mobile group(P<0.05).Both groups displayed significant low-frequency air-bone gaps(ABG),indicative of conductive hearing loss;The mobile group demonstrated significantly larger ABG in the high-frequency range(1 000-4 000 Hz)compared to the fixation group(P<0.05).CONCLUSION Isolated congenital middle ear anomalies typically present as moderate-to-severe conductive hearing loss,predominantly affecting low frequencies.Cluster analysis identified three audiological parameters with predictive potential for stapes footplate fixation:1.ABG magnitude at 1 000-4 000 Hz,2.slope of the bone conduction threshold curve at 250-1 000 Hz,3.slope of the bone conduction threshold curve at 1 000-4 000 Hz.The combination of a Carhart notch,a flat-to-rising air conduction curve,and negative HRCT findings serves as a red-flag profile for stapes footplate fixation.