Effect of Tympanic Membrane Perforation and Middle Ear Space Volume with Sound Transmission in Unilateral Chronic Otitis Media

Introduction: In India, the incidence of chronic otitis media (COM) is around 30%, with a prevalence rate of 60/1000 population in urban and 46/1000 in rural areas. The impact of this condition on auditory function is multifaceted, with factors such as the site and size of the tympanic membrane (TM) perforation, as well as the volume of the middle ear air space, playing crucial roles in shaping the transmission of sound. Understanding the interplay between these variables is essential for optimizing clinical management and improving outcomes for patients with unilateral COM. Objective: The objective of this study was to study the effect of TM perforation and middle ear space volume with sound transmission in unilateral COM. Methods: One hundred and twenty-seven patients were included in this study who visited ear, nose, and throat outpatient department and met all criteria in 1-year study. The size and site of TM perforation have been examined. The perforation area is calculated by imprinting a graph grid measuring 1 mm × 1 mm square over a transparent OHP sheet and cutting it to an oval shape. Middle ear space volume has been calculated using impedance audiometry. Patients’ hearing loss is being compared with different sizes and perforation sites. Hearing loss is correlated with middle ear space volume. Results: Out of 127 patients, the majority of patients (42%) are of middle age (26–35 years). Males ( n = 92) were predominant than females ( n = 35). Fifty-five percent of patients have large perforation (area >30 mm 2 ). Middle ear air space volume is inversely proportional to hearing loss ( P < 0.001). Low volume has a mean AB gap of 35.37 dB HL. Posterior perforation (35.6) has more hearing loss as compared to anterior perforation (25.4) ( P < 0.001). Conclusion: Hearing loss is directly proportional to the size of perforation and inversely proportional to middle ear space volume. Hearing loss is more for posterior perforation as compared to anterior perforations. However, there is no correlation between hearing loss and the age and gender of patients.