Affiliations
doi: 10.29271/jcpsppg.2025.01.85ABSTRACT
Objective: To determine the association of the size of the tympanic membrane perforation with post-myringoplasty hearing outcomes by assessing graft uptake, air-bone gap (ABG) reduction, word recognition score (WRS), and speech reception threshold (SRT) parameters.
Study Design: A cross-sectional study.
Place and Duration of the Study: Department of Otorhinolaryngology, Khyber Teaching Hospital, Peshawar, Pakistan, from January 2024 to February 2025.
Methodology: A total of 200 patients undergoing myringoplasty were included in the study. The participants were stratified into three groups based on perforation size: Small (Group 1), medium (Group 2), and large (Group 3). Preoperative and three-month postoperative pure-tone audiometry (PTA), WRS, and SRT scores were recorded. Paired t-test was applied for intra-group comparisons, while one-way ANOVA was used for inter-group comparisons.
Results: Graft uptake rates were comparable across the groups: 96.34% in Group 1, 95.31% in Group 2, and 88.88% in Group 3 (p = 0.17). Among patients with successful graft uptake, significant improvements were observed in ABG, WRS, and SRT scores in all groups (p <0.01), except for SRT in Group 1 (p = 0.82). The mean improvement in ABG was significantly greater in Group 3 (30.41 ± 5.09 dB) compared to Group 1 (20.83 ± 4.69 dB) and Group 2 (19.90 ± 4.28 Db; p <0.01). Similarly, the mean improvement in WRS was higher in Group 3 (2.72 ± 1.14%) compared to Group 1 (0.6 ± 1.04%) and Group 2 (0.4 ± 1.16%; p <0.01). Additionally, SRT improvement was significantly greater in Group 3 (16.68 ± 3.53 dB) compared to Group 1 (0.15 ± 5.91 dB) and Group 2 (4.98 ± 3.62 dB) (p <0.01).
Conclusion: Although patients with larger perforations had slightly lower graft uptake rates, they demonstrated significant improvement in hearing. These findings suggest that endoscopic myringoplasty effectively restores hearing across all perforation sizes, with larger perforations benefiting the most in terms of ABG reduction, WRS enhancement, and SRT improvement.
Key Words: Myringoplasty, Tympanic membrane perforation, Speech reception threshold test, Pure-tone audiometry.
INTRODUCTION
Chronic otitis media (COM) is a major health issue, particularly in developing countries.1 The mucosal type, characterised by tympanic membrane perforation, is the most prevalent kind of COM.2 Key symptoms include hearing loss and otorrhoea, which can severely impact language development, communication skills, and academic performance, especially in children and young adults.3
Hearing loss and the dimensions of tympanic perforation have a strong quantitative relationship. The larger the perforation, the greater the auditory deficits.4 Myringoplasty is the surgical procedure of choice for COM. Its primary aim is to repair the perforation; however, it also improves the patient’s hearing. Advancements in microsurgical techniques, anaesthesia, introduction of endoscopes, and biomaterials have enhanced the success of this procedure.5
Several prognostic factors influence the outcomes of myringoplasty, including the site of the perforation, the active or inactive status of COM, the condition of the opposite ear, and the graft material used.6 Regarding the size of perforation, literature suggests that the smaller perforations have a higher graft uptake rate, while the larger ones are associated with an increased risk of graft failure.7 However, it has also been postulated that while the graft uptake may vary with the perforation size, post-myringoplasty hearing outcomes remain similar regardless of the perforation dimensions.8 Some studies suggest that the choice of graft material is the main determinant of hearing outcomes, especially in larger perforations.9 Notably, the literature lacks sufficient evidence on the effect of perforation size on post-myringoplasty speech recognition outcomes.
This study aimed to evaluate post-myringoplasty hearing outcomes in different perforation sizes, in terms of audiometry, speech reception, and recognition abilities.
METHODOLOGY
This cross-sectional study was conducted at the Department of Otorhinolaryngology, Khyber Teaching Hospital, Peshawar, Pakistan, from January 2024 to February 2025 after obtaining approval from the hospital’s Institutional Review Board (Approval No: 792/DME/KMC, Issued on 07/12/2023). The sample size was determined using the WHO sample size calculation formula, incorporating an anticipated rate of hearing improvement following myringoplasty of 60.6%, a margin of error of 7%, and a confidence level of 95%, yielding a required sample of 188 participants. Patients were enrolled through a non-probability consecutive sampling technique.
Inclusion criteria included individuals aged 18 to 60 years, of either gender, presenting with a dry perforated tympanic membrane for a duration exceeding 12 weeks, a functioning Eustachian tube, intact ossicular chain, and conductive hearing loss with preserved cochlear function. Exclusion criteria encompassed patients with a history of prior middle ear surgery or revision myringoplasty, external ear pathologies, mixed hearing loss on pure-tone audiometry (PTA), or pathological changes in the middle ear mucosa, such as polypoidal or atrophic mucosa, cholesteatoma, or granulation tissue. Individuals with systemic medical conditions affecting wound healing such as diabetes mellitus were also excluded.
All the subjects underwent otoendoscopy using a zero-degree endoscope. Photographs were taken and visually assessed by two investigators for the perforation size independently. Any discrepancies between the investigators were resolved by involving a third researcher.
Table I: Descriptive details of the population.
|
No. of patients (n) |
200 |
|
Age in years (mean ± SD) |
29.62 ± 10.25 |
|
Gender (male:female) |
83:117 |
|
Side of ear operated (right:left) |
111:89 |
|
Types of perforation Medium n (%) Large n (%) |
- |
The participants were stratified into three groups based on the size of the tympanic membrane perforation. Group 1 included those with small perforations (<25% of the tympanic membrane), Group 2 had medium-sized perforations (25–50%), and Group 3 had large perforations (>50%). Each subject underwent endoscopic permeatal myringoplasty with an underlay technique using the temporalis fascia as graft material. Patients with bilateral disease underwent unilateral myringoplasty of the poorer ear. All participants underwent preoperative and three-month postoperative assessments, including PTA, word recognition score (WRS), and speech reception threshold (SRT). Only patients who had successful graft uptake were included in the comparative analysis of post-myringoplasty hearing outcomes.
Statistical analysis was conducted using SPSS version 23.0. Data normality was assessed using the Shapiro-Wilk test. Continuous variables were summarised as means ± standard deviations (SD), while categorical variables were presented as frequencies and percentages. Paired t-tests were used to compare preoperative and postoperative measures within groups. Between-group comparisons of ABG, WRS, and SRT were conducted using one-way ANOVA, followed by post hoc analysis when required. A p-value of <0.05 was considered statistically significant.
RESULTS
A total of 200 patients (200 ears) were enrolled. The descriptive details of the population are shown in Table I. Graft uptake rates were comparable across the groups: 96.34% in Group 1, 95.31% in Group 2, and 88.88% in Group 3 (p = 0.17, Table II). Postoperatively, 12 patients had residual perforations at the 3rd month mark, while the rest had no notable complications.
All the groups showed significant improvement in ABG and WRS (p <0.01). One-way ANOVA followed by post hoc analysis revealed that the mean improvement in ABG and WRS was significantly greater in Group 3 compared to Group 1 and 2 (Table III, IV).
Among patients with successful graft uptake, significant improvements were observed in SRT in all groups (p <0.01), except in Group 1 (p = 0.82). SRT improvement was significantly greater in Group 3 compared to Group 1 and 2 (p <0.01, Table V).
Other than graft failure in 12 (6%) patients, 11 (5.5%) patients had tinnitus, 5 (2.5%) had temporary vertigo, and 14 (7%) had atelectatic middle ear.
Table II: Comparison of graft uptake among all the groups.|
Group no. |
Types of perforation |
Graft success n/N (%) |
Graft failure n/N (%) |
Chi-square (p-value) |
|
1. |
Small |
79/82 (96.34) |
3/82 (3.65) |
0.17 |
|
2. |
Medium |
61/64 (95.31) |
3/64 (4.68) |
|
|
3. |
Large |
48/54 (88.88) |
6/54 (11.11) |
|
|
|
Total |
188/200 (94) |
12/200 (6) |
Table III: The comparison of air-bone gap (ABG) closure among all the groups.
|
Group No. |
Types of perforation |
Preoperative ABG in dB (mean ± SD) |
Postoperative (mean ± SD) |
Difference
|
Paired (p-values) |
One-way ANOVA |
|
1. |
Small |
26.00 ± 2.86 |
5.16 ± 3.53 |
20.83 ± 4.69 |
<0.01 |
<0.01 |
|
2. |
Medium |
29.75 ± 3.60 |
9.85 ± 2.12 |
19.9 ± 4.28 |
<0.01 |
|
|
3. |
Large |
44.12 ± 4.45 |
13.70 ± 2.71 |
30.41 ± 5.09 |
<0.01 |
Table IV: The comparison of improvement in word recognition score (WRS) among all the groups.
|
Group No. |
Types of |
Preoperative WRS as % (mean ± SD) |
Postoperative 3rd month WRS as % (mean ± SD) |
Difference
|
Paired t-test (p-values) |
One-way ANOVA |
|
1. |
Small |
99.08 ± 0.77 |
99.69 ± 0.64 |
0.6 ± 1.04 |
<0.01 |
<0.01 |
|
2. |
Medium |
98.57 ± 0.82 |
98.98 ± 0.78 |
0.4 ± 1.16 |
<0.01 |
|
|
3. |
Large |
96.56 ± 1.00 |
99.29 ± 0.84 |
2.72 ± 1.14 |
<0.01 |
Table V: The comparison of improvement in speech reception threshold (SRT) among all the groups.
|
Group No. |
Types of perforation |
Preoperative SRT in dB (mean ± SD) |
Postoperative 3rd month SRT in dB (mean ± SD) |
Difference (mean ± SD) |
Paired t-test (p-values) |
One-way ANOVA (p-values) |
|
1. |
Small |
11.40 ± 4.42 |
11.25 ± 4.39 |
0.15 ± 5.91 |
0.82 |
<0.01 |
|
2. |
Medium |
22.04 ± 2.23 |
17.06 ± 2.44 |
4.98 ± 3.62 |
<0.01 |
|
|
3. |
Large |
38.72 ± 2.86 |
22.04 ± 2.05 |
16.68 ± 3.53 |
<0.01 |
DISCUSSION
Endoscopic myringoplasty primarily aims to achieve an intact tympanic membrane and dry ear, followed by improvement in hearing.10 However, the impact of the size of TM perforation on these outcomes remains poorly documented.
The anatomical success rate of myringoplasty is defined as an intact graft after at least one month of surgery.11,12 Its range is widely reported in literature from 66.6% and 74.4% by Black et al. and Pinar et al., respectively, to 95% and 97% by Begh et al. and Sheehy et al., respectively.11,13-15 In the current study, the overall graft success rate after 3 months was 94%, with small perforations showing the highest uptake (96.34%) and large perforations the lowest (88.88%). Similar results were observed by Zhang et al., who reported a 100% graft success rate for small perforations, decreasing to 93.7% for medium and 89.2% for large perforations.16
The functional success of myringoplasty is defined as the postoperative ABG ≤20dB. All three groups achieved satisfactory outcomes in this regard.17 However, the patients with larger perforations (Group 3) demonstrated significantly greater ABG improvement than those with small or medium-sized perforations. This suggests that larger perforations, despite slightly lower graft uptake rates, may provide more substantial auditory gains postoperatively. Ersozlu et al. reported a difference in graft uptake rates between smaller and larger perforations but found that perforation size had no significant effect on hearing outcomes.8
PTA, though commonly used for hearing assessment, has limitations as it does not always correlate with a patient’s real- world communication ability and is influenced by cognitive factors.18 To address this, speech audiometry, including WRS and SRT, provides a more functional evaluation of hearing outcomes. WRS is the percentage of words that a patient correctly detects and repeats. SRT is the sound level at which 50% of the words presented to the patient are successfully repeated.18,19 In the current study, WRS improved significantly across all groups, with the largest improvement observed in Group 3. Similarly, SRT improved significantly in Group 2 and 3, while the change in Group 1 was not statistically significant. Alain et al. found that for larger or marginal perforations, SRT improved from 38 dB to 24 dB, whereas for central perforations, the SRT improved to 26 dB, concluding an insignificant difference between the groups.20 On the contrary, the greater improvement in both WRS and SRT in Group 3 in the current study reinforces the idea that patients with larger tympanic membrane perforations benefit the most from myringoplasty in terms of both auditory and speech perception gains.
This study is limited in its scope by being single-centred and involving subjective audiometric evaluation. Moreover, excluding patients with graft failure from hearing assessment can likely overestimate the benefits of myringoplasty. Keeping the objectives of this study in mind, this exclusion was inevitable.
CONCLUSION
Patients with larger tympanic membrane perforations had slightly lower graft uptake rates than those with small or medium-sized perforations. However, they demonstrated significantly greater postoperative hearing improvements, particularly in ABG, WRS, and SRT. Those with small or medium-sized perforations also had postoperative improvement in hearing outcomes though this change was insignificant when compared to larger perforations. These findings suggest that endoscopic myringoplasty effectively restores hearing across all perforation sizes, with larger perforations benefiting the most in ABG closure, WRS enhancement, and SRT improvement.
ETHICAL APPROVAL:
This study was conducted in accordance with the ethical standards of the Institutional Review Board of Khyber Teaching Hospital, Peshawar, Pakistan (Approval No. 792/DME/KMC issued on 07/12/2023). The research was conducted in accordance with the ethical guidelines and regulations set forth by the institution, strictly adhering to the principles of the Declaration of Helsinki.
PATIENTS’ CONSENT:
Informed consent was obtained from each participant included in this study.
COMPETING INTEREST:
The authors declared no conflict of interest.
AUTHORS’ CONTRIBUTION:
JAQ: Conception, study design, and drafting of the manuscript.
NL: Manuscript drafting and statistical analysis.
IUD: Interpretation of results and critical analysis of the final manuscript.
ON: Interpretation of results and drafting of the manuscript.
All authors approved the final version of the manuscript to be published.
REFERENCES