ASSOCIATION OF HEARING THRESHOLDS WITH FREQUENCY, TYMPANIC MEMBRANE PERFORATION SIZE, AND DISEASE DURATION IN INACTIVE MUCOSAL CHRONIC OTITIS MEDIA

Abstract

Background: Inactive mucosal chronic otitis media (COM) is a middle-ear condition characterized by a persistent tympanic membrane perforation without active ear discharge. It is an important cause of preventable conductive hearing loss, particularly in developing countries. Hearing impairment may be influenced by several factors, including tympanic membrane perforation size, disease duration, and test frequency. The relationship between these factors requires further clinical evaluation. Methods: This hospital-based observational study included 100 perforated ears of patients diagnosed with inactive mucosal chronic otitis media. Demographic characteristics, tympanic membrane perforation size, disease duration, and audiological findings were recorded. Hearing thresholds, pure-tone average (PTA), and air-bone gap (ABG) were assessed using pure-tone audiometry at different frequencies. Statistical analysis was performed to evaluate the relationship between hearing thresholds and the clinical parameters. Results: Females constituted 56% of the participants, while males constituted 44%. Large central tympanic membrane perforation was the most common perforation type (49%), followed by moderate central perforation (30%). Mild conductive hearing loss was observed in 44% of participants, moderate hearing loss in 38%, and moderately severe hearing loss in 18%. Mean hearing thresholds were higher at high frequencies (46.3 ± 11.5 dB HL) than at low frequencies (28.4 ± 8.7 dB HL). Mean PTA increased with disease duration, from 31.6 ± 6.4 dB among patients with disease duration of less than 5 years to 47.5 ± 10.3 dB among those with disease duration of more than 10 years. Hearing loss also increased with increasing tympanic membrane perforation size, with subtotal perforations demonstrating the highest mean PTA (50.8 ± 9.4 dB). The mean ABG increased from 24.2 ± 5.4 dB at 500 Hz to 30.9 ± 7.1 dB at 2000 Hz. Conclusion: Hearing impairment in patients with inactive mucosal chronic otitis media was associated with tympanic membrane perforation size, disease duration, and test frequency. Larger perforations and longer disease duration were associated with greater hearing impairment, while hearing thresholds and ABG showed higher values at higher frequencies.