Chronic otitis media (COM) remains one of the most common causes of preventable hearing loss, particularly in developing countries, where overcrowding, poor hygiene, recurrent upper respiratory tract infections, and limited access to healthcare contribute significantly to its prevalence. The World Health Organization estimates that chronic otitis media affects over 65–330 million individuals worldwide, with a significant proportion suffering from disabling hearing impairment. Among its various clinical types, chronic otitis media of the mucosal type (tubotympanic disease) is generally considered a “safe” form but is nevertheless associated with varying degrees of conductive hearing loss and morbidity.[1] Inactive mucosal chronic otitis media is characterized by a dry central tympanic membrane perforation without active discharge or cholesteatoma. Despite being considered relatively benign, patients often experience significant hearing impairment, which can adversely affect communication, academic performance, and quality of life. The degree of hearing loss in such cases is influenced by multiple factors, including the size and site of the tympanic membrane perforation, ossicular chain status, middle ear volume, and middle ear mucosal condition.[2] Among these factors, the size of the tympanic membrane perforation plays a crucial role in determining the extent of conductive hearing loss. Larger perforations reduce the effective vibratory area of the tympanic membrane and alter the impedance matching mechanism of the middle ear, thereby reducing sound transmission to the cochlea. Several experimental and clinical studies have demonstrated a direct relationship between perforation size and degree of hearing loss; however, variations exist based on methodological differences, population characteristics, and methods of perforation assessment.[3] Pure tone audiometry (PTA) remains the gold standard for quantifying hearing loss, while otoscopic and otoendoscopic examinations provide accurate assessment of tympanic membrane morphology. Correlating perforation size with audiological findings not only aids in prognostication but also assists in counseling patients regarding expected hearing outcomes and surgical planning for tympanoplasty.[4] Aim To study the correlation between tympanic membrane perforation size and the degree of hearing loss in patients with inactive mucosal chronic otitis media. Objectives 1. To assess the size of tympanic membrane perforation in patients diagnosed with inactive mucosal chronic otitis media. 2. To evaluate and correlate the degree of hearing loss with the size of tympanic membrane perforation using pure tone audiometry.

Source of Data Patients attending the Department of Otorhinolaryngology at a tertiary care teaching hospital who were diagnosed with inactive mucosal chronic otitis media were included in the study. Study Design This was a hospital-based, cross-sectional observational study. Study Location The study was conducted in the Department of Otorhinolaryngology and Audiology Unit of a tertiary care hospital. Study Duration The study was conducted over a period of 12 months. Sample Size A total of 200 patients diagnosed with inactive mucosal chronic otitis media were included in the study. Inclusion Criteria • Patients aged 15–60 years • Diagnosed cases of inactive mucosal chronic otitis media • Presence of central tympanic membrane perforation • Dry ear for at least 6 weeks • Patients willing to give informed consent Exclusion Criteria • Active ear discharge or squamosal type of chronic otitis media • History of previous ear surgery • Presence of ossicular chain discontinuity or cholesteatoma • Sensorineural or mixed hearing loss • Patients with congenital ear anomalies Procedure and Methodology After obtaining informed consent, detailed history taking and clinical examination were performed. Otoscopic and otoendoscopic examinations were used to assess the size and site of tympanic membrane perforation. Perforations were categorized based on the percentage of tympanic membrane involvement (small, medium, large, or subtotal). All patients underwent pure tone audiometry using a calibrated audiometer in a sound-treated room. Air conduction and bone conduction thresholds were recorded at standard frequencies (500 Hz, 1 kHz, 2 kHz, and 4 kHz), and the average air-bone gap was calculated. Hearing loss was categorized as mild, moderate, or severe based on standard WHO classification. Sample Processing Audiological data and otoscopic findings were recorded in a predesigned proforma. Tympanic membrane perforation size was documented using standardized otoscopic grading. Data Collection Data collected included demographic details, laterality of disease, size of perforation, and degree of hearing loss. All findings were entered into a structured data collection sheet. Statistical Methods Data were entered into Microsoft Excel and analyzed using SPSS software version 25. Descriptive statistics were expressed as mean ± standard deviation and percentages. Correlation between perforation size and hearing loss was assessed using Pearson’s correlation coefficient. A p-value of <0.05 was considered statistically significant.

Table 1: Correlation between tympanic membrane perforation size and degree of hearing loss (N = 200) Measure Total (N=200) Mean ± SD / n(%) Test of significance Effect size (95% CI) p-value Perforation size (%) 34.6 ± 18.6 PTA (Air conduction, dB HL) 31.7 ± 9.8 Air–bone gap (ABG, dB) 27.4 ± 9.3 Correlation: Perforation size (%) vs PTA (AC, dB HL) Pearson correlation r = 0.59 (0.49 to 0.67) <0.001 Correlation: Perforation size (%) vs ABG (dB) Pearson correlation r = 0.63 (0.54 to 0.71) <0.001 Linear regression: ABG predicted by perforation size Linear regression (t-test for slope) +3.15 dB ABG per 10% increase (2.61 to 3.69) <0.001 Table 1 demonstrates a strong and statistically significant relationship between tympanic membrane perforation size and degree of hearing loss among patients with inactive mucosal chronic otitis media. The mean perforation size was 34.6 ± 18.6%, while the mean pure tone average (PTA) was 31.7 ± 9.8 dB HL, and the mean air–bone gap (ABG) was 27.4 ± 9.3 dB. Pearson’s correlation analysis revealed a strong positive correlation between perforation size and PTA (r = 0.59; 95% CI: 0.49–0.67; p < 0.001), indicating that larger perforations were associated with greater degrees of hearing loss. Similarly, a strong positive correlation was observed between perforation size and ABG (r = 0.63; 95% CI: 0.54–0.71; p < 0.001). Linear regression analysis further demonstrated that for every 10% increase in tympanic membrane perforation size, the air–bone gap increased by approximately 3.15 dB (95% CI: 2.61–3.69; p < 0.001). Table 2 outlines the distribution and determinants of tympanic membrane perforation size among the study population. Of the 200 patients, the most common category was medium-sized perforations (25–49%) seen in 35.5% of cases, followed by small perforations in 31.5%, large perforations in 22.0%, and subtotal perforations in 11.0%. The overall mean perforation size was 34.6 ± 18.6%. When stratified by sex, males demonstrated a slightly higher mean perforation size (36.9 ± 19.1%) compared to females (32.1 ± 17.7%), although this difference did not reach statistical significance (p = 0.068). Analysis across age groups showed a significant increasing trend in perforation size with advancing age. Patients aged ≤29 years had a mean perforation size of 29.6 ± 16.8%, those aged 30–44 years had 35.7 ± 18.1%, and patients aged ≥45 years had the largest mean perforation size at 40.4 ± 19.2%. This difference was statistically significant (ANOVA F = 5.95, p = 0.003), with a moderate effect size (η² = 0.057). Laterality analysis revealed no significant difference between right and left ear involvement (p = 0.674), indicating symmetrical disease distribution. Table 2: Assessment of tympanic membrane perforation size in inactive mucosal COM (N = 200) Variable Category Total (N=200) n(%) / Mean ± SD Test of significance Effect size (95% CI) p-value Perforation size category Small (<25%) 63 (31.5) Medium (25–49%) 71 (35.5) Large (50–74%) 44 (22.0) Subtotal (≥75%) 22 (11.0) Mean perforation size (%) Overall 34.6 ± 18.6 Sex Male (n=112) 36.9 ± 19.1 Welch t = 1.84 Mean diff (M−F) = +4.8 (−0.35 to +9.95) 0.068 Female (n=88) 32.1 ± 17.7 Age group (years) ≤29 (n=78) 29.6 ± 16.8 One-way ANOVA F = 5.95 η² = 0.057 0.003 30–44 (n=69) 35.7 ± 18.1 ≥45 (n=53) 40.4 ± 19.2 Side involved Right ear 97 (48.5) χ² = 0.18 Difference = 3.0% (−7.8 to +13.8) 0.674 Left ear 103 (51.5) Table 3: Hearing loss severity and its correlation with perforation size using PTA (N = 200) A) Perforation size category vs hearing loss category Perforation size category Mild n(%) Moderate n(%) Moderately severe n(%) Severe n(%) Test of significance Effect size p-value Small (n=63) 40 (63.5) 20 (31.7) 3 (4.8) 0 (0.0) Medium (n=71) 28 (39.4) 34 (47.9) 8 (11.3) 1 (1.4) χ² = 68.02 (df=9) Cramér’s V = 0.337 <0.001 Large (n=44) 9 (20.5) 26 (59.1) 8 (18.2) 1 (2.3) Subtotal (n=22) 2 (9.1) 7 (31.8) 7 (31.8) 6 (27.3) B) Mean PTA (Air conduction) across perforation size categories Perforation size category PTA (AC, dB HL) Mean ± SD Test of significance Effect size (95% CI) p-value Small (n=63) 24.6 ± 6.8 Medium (n=71) 30.8 ± 7.4 One-way ANOVA F = 45.76 η² = 0.412 <0.001 Large (n=44) 36.9 ± 8.1 Subtotal (n=22) 44.2 ± 9.0 Pairwise (Welch): Subtotal − Small Mean diff = +19.6 (15.3 to 23.9) <0.001 Table 3 illustrates a clear gradation in hearing loss severity with increasing perforation size. In patients with small perforations, the majority had mild hearing loss (63.5%), with very few exhibiting moderate or moderately severe loss and none having severe loss. In contrast, patients with medium-sized perforations predominantly exhibited moderate hearing loss (47.9%), while those with large and subtotal perforations showed a progressive shift toward moderately severe and severe hearing loss. Notably, 27.3% of patients with subtotal perforations had severe hearing loss. The association between perforation size category and degree of hearing loss was highly significant (χ² = 68.02, p < 0.001), with a moderate-to-strong effect size (Cramér’s V = 0.337). Further analysis of mean PTA values reinforced this trend. Mean PTA increased steadily from 24.6 ± 6.8 dB in small perforations to 30.8 ± 7.4 dB in medium, 36.9 ± 8.1 dB in large, and 44.2 ± 9.0 dB in subtotal perforations. One-way ANOVA demonstrated a highly significant difference across groups (F = 45.76, p < 0.001), with a large effect size (η² = 0.412). Pairwise comparison showed that patients with subtotal perforations had a mean PTA that was 19.6 dB higher than those with small perforations (95% CI: 15.3–23.9; p < 0.001).

The present study evaluated the relationship between tympanic membrane (TM) perforation size and the degree of hearing loss in patients with inactive mucosal chronic otitis media (COM). The findings demonstrate a strong and statistically significant association between increasing perforation size and worsening conductive hearing loss, which is consistent with established otological principles and previously published literature. In the current study, the mean perforation size was 34.6 ± 18.6%, with a corresponding mean air-conduction threshold of 31.7 ± 9.8 dB HL and mean air–bone gap (ABG) of 27.4 ± 9.3 dB. A strong positive correlation was observed between perforation size and hearing loss (r = 0.59 for PTA; r = 0.63 for ABG, p < 0.001). This indicates that as the effective vibratory area of the tympanic membrane decreases, the efficiency of sound transmission across the middle ear diminishes proportionally. Similar findings were reported by Gupta K et al. (2025)[5], who demonstrated that increasing perforation size significantly reduces sound pressure gain at the oval window due to altered middle-ear mechanics. Likewise, Rana AK et al. (2020)[2] emphasized that loss of the tympanic membrane’s transformer function directly increases conductive hearing loss. The linear regression analysis in the present study showed that every 10% increase in perforation size resulted in an average increase of 3.15 dB in ABG, reinforcing the quantitative relationship between anatomical damage and functional deficit. Comparable observations were made by Kim DK et al. (2021)[6], who reported a near-linear rise in conductive hearing loss with increasing perforation area, particularly when the perforation exceeded one-third of the tympanic membrane. Regarding perforation size distribution, medium-sized perforations were most common (35.5%), followed by small (31.5%), large (22%), and subtotal perforations (11%). This pattern is comparable to findings by Castelhano L et al. (2022)[4], who also reported a predominance of medium-sized perforations in inactive mucosal COM. Age-wise analysis in the present study demonstrated a significant increase in perforation size with advancing age (p = 0.003), which may reflect longer disease duration and cumulative middle ear damage. Similar age-related trends have been reported by Soni S et al. (2023)[7], who noted larger and more persistent perforations in older individuals with chronic otitis media. Sex-wise analysis revealed no statistically significant difference in perforation size between males and females, aligning with findings from Mukherjee Y et al. (2025)[8], who also observed no sex predilection in perforation dimensions or hearing outcomes. Additionally, no significant difference was noted between right and left ear involvement, consistent with the bilateral disease distribution reported in earlier epidemiological studies. The relationship between perforation size and severity of hearing loss was further highlighted in Table 3. Patients with small perforations predominantly exhibited mild hearing loss, whereas those with large and subtotal perforations showed a marked shift toward moderately severe and severe hearing loss. The strong association (χ² = 68.02, p < 0.001; Cramér’s V = 0.337) indicates a clinically meaningful gradient of hearing impairment with increasing perforation size. Similar trends were documented by Soni S et al. (2023)[7], who reported that subtotal perforations were associated with significantly higher air–bone gaps compared to small or medium perforations. Mean PTA values increased progressively from 24.6 dB in small perforations to 44.2 dB in subtotal perforations, with a large effect size (η² = 0.412). This stepwise deterioration aligns with findings by Rasheed AM. (2023)[9], who demonstrated that larger perforations compromise the acoustic coupling mechanism and reduce middle-ear impedance matching, resulting in greater conductive loss.

The present study demonstrates a strong and statistically significant correlation between the size of tympanic membrane perforation and the degree of hearing loss in patients with inactive mucosal chronic otitis media. As the perforation size increased, a proportional rise in both pure tone average and air–bone gap was observed, indicating progressive impairment of middle ear sound conduction. Patients with small perforations predominantly exhibited mild hearing loss, whereas those with large and subtotal perforations showed moderate to severe degrees of hearing impairment. A significant positive correlation was observed between perforation size and hearing thresholds, with regression analysis confirming that every 10% increase in perforation size resulted in a clinically meaningful rise in hearing loss. The study also demonstrated that increasing age was associated with larger perforation size, suggesting a possible cumulative effect of chronic disease duration. No significant association was observed with sex or laterality of the ear involved. These findings reinforce the concept that the extent of tympanic membrane damage is a key determinant of conductive hearing loss in inactive mucosal chronic otitis media. Early identification and timely surgical intervention, particularly in patients with larger perforations, may help prevent progression of hearing impairment and improve auditory outcomes. The study highlights the importance of routine audiological assessment and meticulous evaluation of perforation size in clinical practice. LIMITATIONS OF THE STUDY 1. The study was conducted at a single tertiary care center, which may limit the generalizability of the findings to other populations or healthcare settings. 2. The cross-sectional study design did not allow assessment of temporal changes or postoperative hearing outcomes following tympanoplasty. 3. Ossicular chain status was not evaluated intraoperatively or radiologically, which could have influenced the degree of hearing loss. 4. Middle ear volume and Eustachian tube function were not assessed, both of which may affect sound conduction. 5. Only patients with inactive mucosal disease were included; therefore, results cannot be extrapolated to active or squamosal chronic otitis media. 6. Audiological assessment was limited to pure tone audiometry without speech audiometry or tympanometry, which may have provided additional functional insights.

1. Kolluru K, Kumar S, Upadhyay P. A study of correlation between tympanic membrane perforation size with hearing loss in patients with inactive mucosal chronic otitis media. Otology & Neurotology. 2021 Jan 1;42(1):e40-4. 2. Rana AK, Upadhyay D, Yadav A, Prasad S. Correlation of tympanic membrane perforation with hearing loss and its parameters in chronic otitis media: an analytical study. Indian Journal of Otolaryngology and Head & Neck Surgery. 2020 Jun;72(2):187-93. 3. Anand R, Verma V, Singh AB, Kumar S, Singh HP, Mishra A, Chandra M. To assess the effect of duration and size of perforation of tympanic membrane on hearing in patients of chronic otitis media mucosal type. Annals of African Medicine. 2025 Jul 1;24(3):610-6. 4. Castelhano L, Correia F, Colaço T, Reis L, Escada P. Tympanic membrane perforations: the importance of etiology, size and location. European Archives of Oto-Rhino-Laryngology. 2022 Sep;279(9):4325-33. 5. Gupta K, Jadia S, Qureshi S, Vijay S, Gupta B. Effect of Tympanic Membrane Perforation and Middle Ear Space Volume with Sound Transmission in Unilateral Chronic Otitis Media. Indian Journal of Otology. 2025 Oct 1;31(4):242-5. 6. Kim DK, Choi H, Lee H, Hwang SH, Kang JM, Seo JH. Effects of tympanic membrane perforation, middle ear cavity volume, and mastoid aeration on hearing impairment. American Journal of Otolaryngology. 2021 May 1;42(3):102901. 7. Soni S, Malhotra V, Sharma R, Passey JC. Sensorineural hearing loss in unilateral mucosal type of chronic otitis media. Indian Journal of Otolaryngology and Head & Neck Surgery. 2023 Sep;75(3):2149-54. 8. Mukherjee Y, Goyal I, Chatterji P, Dasgupta A. Predictors of cochlear involvement in patients with mucosal type of chronic otitis media: a cross-sectional analysis. The Egyptian Journal of Otolaryngology. 2025 Oct 29;41(1):186. 9. Rasheed AM. Does the Location of a Small Tympanic Membrane Perforation Affect the Dgree of Hearing Loss in Adult Patients with Inactive Mucosal Chronic Suppurative Otitis Media?. The International Tinnitus Journal. 2023 Dec 28;27(2):135-40. 1. Kolluru K, Kumar S, Upadhyay P. A study of correlation between tympanic membrane perforation size with hearing loss in patients with inactive mucosal chronic otitis media. Otology & Neurotology. 2021 Jan 1;42(1):e40-4. 2. Rana AK, Upadhyay D, Yadav A, Prasad S. Correlation of tympanic membrane perforation with hearing loss and its parameters in chronic otitis media: an analytical study. Indian Journal of Otolaryngology and Head & Neck Surgery. 2020 Jun;72(2):187-93. 3. Anand R, Verma V, Singh AB, Kumar S, Singh HP, Mishra A, Chandra M. To assess the effect of duration and size of perforation of tympanic membrane on hearing in patients of chronic otitis media mucosal type. Annals of African Medicine. 2025 Jul 1;24(3):610-6. 4. Castelhano L, Correia F, Colaço T, Reis L, Escada P. Tympanic membrane perforations: the importance of etiology, size and location. European Archives of Oto-Rhino-Laryngology. 2022 Sep;279(9):4325-33. 5. Gupta K, Jadia S, Qureshi S, Vijay S, Gupta B. Effect of Tympanic Membrane Perforation and Middle Ear Space Volume with Sound Transmission in Unilateral Chronic Otitis Media. Indian Journal of Otology. 2025 Oct 1;31(4):242-5. 6. Kim DK, Choi H, Lee H, Hwang SH, Kang JM, Seo JH. Effects of tympanic membrane perforation, middle ear cavity volume, and mastoid aeration on hearing impairment. American Journal of Otolaryngology. 2021 May 1;42(3):102901. 7. Soni S, Malhotra V, Sharma R, Passey JC. Sensorineural hearing loss in unilateral mucosal type of chronic otitis media. Indian Journal of Otolaryngology and Head & Neck Surgery. 2023 Sep;75(3):2149-54. 8. Mukherjee Y, Goyal I, Chatterji P, Dasgupta A. Predictors of cochlear involvement in patients with mucosal type of chronic otitis media: a cross-sectional analysis. The Egyptian Journal of Otolaryngology. 2025 Oct 29;41(1):186. 9. Rasheed AM. Does the Location of a Small Tympanic Membrane Perforation Affect the Dgree of Hearing Loss in Adult Patients with Inactive Mucosal Chronic Suppurative Otitis Media?. The International Tinnitus Journal. 2023 Dec 28;27(2):135-40.