European Journal of Cardiovascular Medicine

Refractory otitis media with effusion (OME) is defined as persistent middle ear effusion despite repeated medical management and multiple ventilation tube (grommet) insertions [1]. OME is common in the pediatric population, with an incidence of up to 90% before school age, whereas its prevalence in adults is relatively low, estimated at approximately 0.6% [2]. Although most children with OME experience spontaneous resolution within three months, approximately 5–10% develop recurrent or persistent disease lasting one year or longer [3].

The pathogenesis of OME is multifactorial, with Eustachian tube dysfunction (ETD) playing a central role. Other contributing factors include acute otitis media, craniofacial anomalies such as Down syndrome and cleft palate, subclinical bacterial infection, and gastroesophageal reflux disease [2]. Long-term grommet insertion remains the conventional treatment for refractory OME [4]. However, repeated ventilation tube insertion does not address the underlying ETD and is often unsuccessful in preventing recurrence. Moreover, it may lead to complications such as tympanic membrane perforation, infection, and tympanosclerosis [5]. Persistent symptoms—including hearing loss, aural fullness, otalgia, tinnitus, and a sensation of pressure or popping in the ears—significantly impair patients’ quality of life [2–4].

ETD contributes to recurrent or persistent middle ear disease by impairing pressure regulation and aeration of the middle ear. While tympanostomy tube insertion temporarily ventilates the middle ear, it does not restore normal Eustachian tube function and may be associated with procedure-related complications [5]. Consequently, balloon Eustachian tuboplasty (BET) has emerged as a novel therapeutic approach targeting the underlying pathophysiology of ETD. First introduced into clinical practice in 2010, BET has been shown to be a safe and effective treatment for ETD, with superior postoperative outcomes compared to conventional medical therapies such as nasal steroids, decongestants, antihistamines, and tympanostomy tube placement alone [6,7].

 Hearing impairment secondary to OME negatively affects speech and language development, educational achievement, employment opportunities, and psychosocial well-being, particularly in children [8].

ETD has been identified as a critical contributing factor in OME by disrupting middle ear ventilation and pressure equilibration. Studies have reported evidence of ETD in up to 70% of patients undergoing middle ear surgery [13]. Therefore, identifying effective therapeutic strategies for patients with OME combined with ETD (OME-ETD) is both urgent and clinically important.

BET has been proposed as a second-line treatment for ETD in cases where adenoidectomy and paracentesis have failed [13,14]. It has also been increasingly applied as an adjunctive surgical approach in the management of otitis media [16]. However, BET alone has demonstrated variable efficacy, with reported symptom improvement rates of approximately 66% [17]. Previous studies have shown that simultaneous BET and hearing reconstruction surgery can significantly improve hearing outcomes and Eustachian tube function in patients with OME-ETD [18]. Furthermore, BET has been suggested as a useful adjunct in the treatment of OME associated with obstructive Eustachian tube dysfunction [19].

Grommet insertion remains one of the most commonly performed surgical procedures for otitis media [20,21]. Nevertheless, it does not correct underlying ETD and is associated with complications such as infection, persistent tympanic membrane perforation, and tympanosclerosis [22]. Emerging evidence suggests that combining BET with grommet insertion may reduce complication rates and improve outcomes in patients with chronic Eustachian tube dysfunction [23].

Therefore, the present study was conducted to evaluate the combined effectiveness of balloon Eustachian tuboplasty and grommet insertion in patients with OME-ETD. Outcomes were assessed in terms of hearing improvement, Eustachian tube function, Eustachian tube inflammation, quality of life, and overall patient satisfaction.

Study Population and Demographic Data

A total of 144 ears from 72 patients diagnosed with Otitis Media with Effusion associated with Eustachian tube dysfunction (OME-ETD) were included in this study. Patients were evaluated between October 2024 and November 2025. The age of the participants ranged from 20 to 60 years. The subjects were divided into two groups: 36 patients underwent balloon Eustachian tuboplasty alone (BET group), and 36 patients underwent balloon Eustachian tuboplasty combined with grommet insertion (BET + Grommet group).

Inclusion and Exclusion Criteria

All enrolled patients fulfilled the following inclusion criteria:

• Diagnosis of OME, common condition where thick, sticky fluid (non-purulent) builds up in the middle ear space behind a healthy eardrum, often after a cold or infection, causing muffled hearing or fullness without pain.
• Diagnosis of severe Eustachian tube dysfunction based on the Eustachian Tube Dysfunction Questionnaire-7 (ETDQ-7), with a total score ≥14.5 (mean score ≥2.1) and persistence of symptoms for more than 3 months [19,25].

Exclusion criteria included:

• Previous treatment for ETD or prior BET procedure
• Patients scheduled for revision surgery
• Congenital ear anomalies
• History of ear surgery within the previous 6 months
• History of head and neck malignancy
• Acute otitis media
• Refractory chronic rhinosinusitis
• Recent use of ototoxic medications
• Pregnancy

Surgical Procedure

All patients underwent balloon Eustachian tuboplasty under general anesthesia. A balloon catheter measuring 20 mm in length and 3 mm in diameter was introduced endoscopically through the nasal cavity into the cartilaginous portion of the Eustachian tube. The balloon was inflated with distilled water to a pressure of 10 bar and maintained for 2 minutes. In the BET + Grommet group, patients additionally underwent ventilation tube (grommet) insertion into the tympanic membrane. All patients were followed up for a period of 12 months.

Hearing Assessment Using Air–Bone Gap (ABG)

Pure-tone audiometry was performed using a Madsen OB922 audiometer (Otometrics, Taastrup, Denmark). Air- and bone-conduction thresholds were measured at frequencies of 500 Hz, 1 kHz, 2 kHz, and 4 kHz. The air–bone gap (ABG) was calculated as the mean difference between air- and bone-conduction thresholds. Surgical success was defined as a postoperative ABG of ≤20 dB [26].

Chronic Otitis Media Outcome Test-15 (COMOT-15)

Disease-specific quality of life was assessed using the Chronic Otitis Media Outcome Test-15 (COMOT-15), which has a total score ranging from 0 to 100 [27]. The questionnaire consists of three subscales: ear symptoms, hearing function, and mental health, along with two additional questions assessing the overall impact of OME on quality of life and the frequency of doctor visits related to OME during the previous six months. Higher COMOT-15 scores indicate poorer quality of life.

Eustachian Tube Inflammation Scale

Eustachian tube inflammation was evaluated using nasal endoscopy. The degree of inflammation of the mucosa at the nasopharyngeal orifice and within the Eustachian tube lumen was graded from normal to severely inflamed (Grade 1–4), according to previously published criteria [28].

Valsalva Maneuver and Patient Satisfaction

A positive Valsalva maneuver was defined as the patient perceiving a characteristic “pop” sensation or sound in the ear during the maneuver. Patient satisfaction was assessed at 6 and 12 months postoperatively and categorized as either satisfied or dissatisfied with the surgical outcome [29].

Statistical Analysis

Statistical analysis was performed using SPSS Statistics software. Continuous variables were expressed as mean ± standard deviation, while categorical variables were presented as frequencies and percentages. The Student’s t-test was used to compare continuous variables between groups, and the paired t-test was applied to compare preoperative and postoperative outcomes within groups. Categorical variables were compared using the chi-square (χ²) test. All statistical tests were two-sided, and a P value <0.05 was considered statistically significant

General Characteristics of OME-ETD Patients

The baseline demographic and clinical characteristics of patients in the BET group and BET + Grommet group were comparable. Detailed patient characteristics are summarized in Table 1.

Table 1: Evaluation of Eustachian tube function using the Eustachian Tube Dysfunction Questionnaire-7 (ETDQ-7).

ETDQ-7 total score of 14.5 (mean item score 2.1)

Table 2: Demographic characteristics of OME-ETD patients in the BET group and BET + Grommet group.

Baseline Demographic Characteristics

The demographic characteristics of patients with OME-ETD in the BET group and the BET + Grommet group are summarized in Table 2. There were no statistically significant differences between the two groups with respect to age (42.3 ± 9.9 years in the BET group vs. 39.5 ± 11.1 years in the BET + Grommet group; P = 0.263), gender distribution (P = 0.477), or laterality of the affected ear (P = 0.347), indicating that the two groups were comparable at baseline.

Air–Bone Gap (ABG) Outcomes

The preoperative and postoperative air–bone gap (ABG) values of OME-ETD patients in both groups are presented in Table 3. Comparative analysis was performed to evaluate hearing improvement following surgery in the BET group and the BET + Grommet group.

Table 3: Preoperative and postoperative air–bone gap (ABG) values in OME-ETD patients in the BET group and BET + Grommet group.

Note: ∗P < 0.05, the intra group comparison with preoperative data.

Improvement in Air–Bone Gap (ABG) after Treatment with BET and Grommet Insertion

Postoperative air–bone gap (ABG) and hearing improvement were evaluated in both groups at 6 and 12 months following surgery (Table 3, Figure 1). The mean preoperative ABG was 23.9 ± 5.2 dB in the BET group and 25.2 ± 4.6 dB in the BET + Grommet group, with no statistically significant difference between the groups (P = 0.265).

At 6 months postoperatively, the mean ABG in the BET + Grommet group (19.0 ± 3.6 dB) was significantly lower than that in the BET group (23.3 ± 10.6 dB; P < 0.05). This difference remained statistically significant at 12 months, with mean ABG values of 15.7 ± 3.5 dB in the BET + Grommet group compared with 22.7 ± 3.7 dB in the BET group (P < 0.05). Within-group analysis demonstrated a significant reduction in ABG at both 6 and 12 months in the BET + Grommet group (both P < 0.05).

A postoperative ABG of ≤20 dB was achieved in 42.2% of patients at 6 months and 44.4% at 12 months in the BET group. In contrast, 53.3% of patients at 6 months and 67.8% at 12 months in the BET + Grommet group achieved an ABG ≤20 dB, indicating superior hearing outcomes with the combined treatment approach.

Table 4: Improvement in ETDQ-7 score, Eustachian tube inflammation scale, and COMOT-15 following treatment with balloon Eustachian tuboplasty combined with grommet insertion.

Improvement in ETDQ-7 Score and Eustachian Tube Inflammation

As shown in Table 4, there were no statistically significant differences between the two groups in preoperative ETDQ-7 scores (BET + Grommet group: 27.3 ± 4.8 vs. BET group: 26.7 ± 4.5; P > 0.05) or Eustachian tube inflammation scale scores (BET + Grommet group: 2.9 ± 0.7 vs. BET group: 3.05 ± 0.7; P > 0.05).

Postoperatively, significant improvement was observed in both groups. The Eustachian tube inflammation scale scores decreased at 6 and 12 months in the BET + Grommet group (6 months: 1.96 ± 0.6; 12 months: 1.5 ± 0.5) as well as in the BET group (6 months: 2.7 ± 0.6; 12 months: 1.96 ± 0.6), with all comparisons reaching statistical significance (P < 0.05). However, the postoperative inflammation scores were significantly lower in the BET + Grommet group than in the BET group at both follow-up points (P < 0.05).

Similarly, ETDQ-7 scores in the BET + Grommet group showed significant reductions at 6 months (21.1 ± 4.1) and 12 months (18.7 ± 3.6) compared with preoperative values (both P < 0.05). The postoperative ETDQ-7 scores were significantly lower in the BET + Grommet group than in the BET group at both time points (P < 0.05). A normal ETDQ-7 score (≤14) was achieved by 13.9% (5/36) and 33.3% (12/36) of patients in the BET + Grommet group at 6 and 12 months, respectively, compared with only 2.8% (1/36) and 8.3% (3/36) in the BET group.

Improvement in Quality of Life (COMOT-15)

Preoperative COMOT-15 scores were comparable between the BET + Grommet group (40.6 ± 10.2) and the BET group (41.3 ± 10.5; P = 0.775), indicating no baseline difference in quality of life. Both groups demonstrated postoperative improvement at 6 and 12 months; however, the degree of improvement was significantly greater in the BET + Grommet group.

At 6 months, the COMOT-15 score decreased to 33.3 ± 7.5 in the BET + Grommet group, compared with 40.3 ± 10.5 in the BET group (P < 0.05). At 12 months, further improvement was observed in the BET + Grommet group (30.6 ± 6.7), whereas minimal change occurred in the BET group (39.7 ± 10.0), with the between-group difference remaining statistically significant (P < 0.05).

Valsalva Maneuver and Patient Satisfaction

The proportion of patients able to perform a positive Valsalva maneuver was significantly higher in the BET + Grommet group than in the BET group at both 6 months (61.1% vs. 38.9%) and 12 months (83.3% vs. 55.6%) postoperatively.

Patient satisfaction rates were also higher in the BET + Grommet group. At 6 months, satisfaction was reported by 77.1% of patients in the BET + Grommet group compared with 58.3% in the BET group. At 12 months, satisfaction increased to 88.9% in the BET + Grommet group, compared with 69.4% in the BET group.

Only minor complications were observed. Two patients in the BET group reported mild postoperative tenderness, which resolved by the 6- and 12-month follow-up visits. No significant difference in adverse events was noted between the two groups.

Grommet insertion has traditionally been the mainstay surgical treatment for Eustachian tube dysfunction (ETD) and recurrent or chronic otitis media, particularly in the presence of persistent middle ear effusion unresponsive to medical therapy. Ventilation tubes help re-establish middle ear aeration, reduce inflammation, facilitate effusion clearance, and improve hearing, making them one of the most commonly performed ambulatory otologic procedures [30,31]. However, grommet insertion does not address the underlying pathophysiology of ETD and is associated with procedure-related complications. In contrast, balloon Eustachian tuboplasty (BET), first described in 2010, represents a minimally invasive technique aimed at restoring physiological Eustachian tube function and has been supported by randomized controlled trials and clinical studies over the past decade [32,33]. Given that BET alone may not consistently achieve optimal symptom control in otitis media, combined approaches using BET with grommet insertion have been increasingly explored in both otitis media and ETD [23,34,35].

Hearing improvement, commonly assessed by the air–bone gap (ABG), remains a key indicator of surgical success [36]. Chen et al. demonstrated that children with otitis media with effusion treated with BET combined with myringotomy and grommet insertion achieved significantly better ABG outcomes at 12 months compared with myringotomy alone [37]. Similarly, studies involving patients with Otitis Media with Effusion and obstructive ETD have shown greater ABG improvement when BET was added to tympanoplasty compared with tympanoplasty alone [19]. In the present study, a significant reduction in ABG was observed in the BET + Grommet group at both 6 and 12 months postoperatively, with superior postoperative ABG values compared with the BET-alone group. Furthermore, according to the Japan Clinical Otology Committee criteria [38], a postoperative ABG of ≤20 dB—indicative of meaningful hearing improvement—was achieved in a higher proportion of patients receiving the combined treatment. These findings reinforce the additive benefit of grommet insertion when combined with BET in improving hearing outcomes in OME-ETD patients.

Effective hearing rehabilitation is generally considered feasible only after restoration of adequate Eustachian tube function [39]. Previous studies have reported improvements in both the structure and function of the Eustachian tube following BET combined with grommet insertion in patients with chronic otitis media with effusion [35]. The Eustachian Tube Dysfunction Questionnaire-7 (ETDQ-7) is a validated tool with high sensitivity and specificity for diagnosing ETD when scores are ≥14.5 [40]. In our study, normalization of ETDQ-7 scores was achieved in a substantially higher proportion of patients in the BET + Grommet group compared with the BET group at both follow-up intervals. Additionally, significant reductions in ETDQ-7 and COMOT-15 scores, along with higher rates of positive Valsalva maneuver, were observed in the combined treatment group, indicating superior restoration of Eustachian tube function and improved disease-specific quality of life.

Mucosal inflammation is recognized as a major contributing factor in ETD [28]. Endoscopic assessment in the present study demonstrated significant postoperative reduction in Eustachian tube inflammation scores in both groups, with more pronounced improvement in the BET + Grommet group. These findings suggest that BET, particularly when combined with grommet insertion, may alleviate ETD by reducing mucosal inflammation, improving middle ear ventilation, and thereby enhancing hearing outcomes and health-related quality of life in patients with OME-ETD.

The primary strength of this study lies in its comprehensive evaluation of functional hearing outcomes, Eustachian tube function, inflammatory status, and patient-reported quality of life following combined BET and grommet insertion. However, several limitations must be acknowledged. First, the retrospective design and absence of a non-surgical control group may limit the strength of causal inference. Second, the follow-up period was limited to 12 months; longer-term outcomes are required to determine the durability of treatment benefits. Future large-scale, prospective randomized controlled trials with extended follow-up are warranted to further validate these findings

Balloon Eustachian tuboplasty combined with grommet insertion demonstrates superior therapeutic efficacy compared with BET alone in patients with OME-ETD. The combined approach results in greater improvement in hearing outcomes, enhanced Eustachian tube function, reduced mucosal inflammation, improved quality of life, and higher patient satisfaction, with minimal complications. This strategy represents an effective and clinically meaningful treatment option for patients with otitis media with effusion associated with Eustachian tube dysfunction.

Conflicts of Interest: The authors declare no conflicts of interest.

1. Kutluhan A, Tarlak B, Cetin H, et al. Mastoid antral ventilation tube; new treatment modality for recurrent otitis media with effusion and its long term results. Int J Clin Exp Med 2015;8:5774-80. .
2. Atkinson H, Wallis S, Coatesworth AP. Otitis media with effusion. Postgrad Med 2015;127:381-5.
3.  Dempster JH, Swan IR. The management of otitis media with effusion in adults. Clin Otolaryngol Allied Sci 1988;13:197-9.
4. Perera R, Glasziou PP, Heneghan CJ, et al. Autoinflation for hearing loss associated with otitis media with effusion. Cochrane Database Syst Rev 2013;(5):CD006285.
5. Hwang SY, Kok S, Walton J. Balloon dilation for Eustachian tube dysfunction: systematic review. J Laryngol Otol 2016;130:S2-S6.
6. Ockermann T, Reineke U, Upile T, et al. Balloon dilatation Eustachian tuboplasty: a clinical study. Laryngoscope 2010;120:1411-6.
7. Poe D, Anand V, Dean M, et al. Balloon dilation of the eustachian tube for dilatory dysfunction: A randomized controlled trial. Laryngoscope 2018;128:1200-6.
8. A. G. M. Schilder, T. Chonmaitree, A. W. Cripps et al., “Otitis media,” Nature Reviews Disease Primers, vol. 2, no. 1, Article ID 16063, 2016. 
9. C. G. Brennan-Jones, K. Head, L. Y. Chong, M. J. Burton, A. G. Schilder, and M. F. Bhutta, “Topical antibiotics for chronic suppurative otitis media,” Cochrane Database of Systematic Reviews, vol. 1, Article ID CD013051, 2018.
10. S. Mahdiani, L. Lasminingrum, and D. Anugrah, “Management evaluation of patients with chronic suppurative otitis media: a retrospective study,” Annals of Medicine and Surgery, vol. 67, Article ID 102492, 2021.
11. A. Master, E. Wilkinson, and R. Wagner, “Management of chronic suppurative otitis media and otosclerosis in developing countries,” Otolaryngologic Clinics of North America, vol. 51, no. 3, pp. 593–605, 2018.
12. R. Mittal, C. V. Lisi, R. Gerring et al., “Current concepts in the pathogenesis and treatment of chronic suppurative otitis media,” Journal of Medical Microbiology, vol. 64, no. 10, pp. 1103–1116, 2015.
13. D. C. Rosario and M. D. Mendez, Chronic Suppurative OtitisStatPearls, Treasure, FL, USA, 2022.
14. I. Todt, F. Oppel, and H. Sudhoff, “Sensorineural hearing loss after balloon eustachian tube dilatation,” Front Surg, vol. 8, Article ID 615360, 2021.
15. B. Demir and C. Batman, “Efficacy of balloon Eustachian tuboplasty on the quality of life in children with Eustachian tube dysfunction,” Acta Oto-Laryngologica, vol. 140, no. 4, pp. 297–301, 2020.
16. Q. Li, Z. Jiang, X. Tian, X. Li, and M. Li, “Clinical observation of chronic recurrent secretory otitis media in adults treated by balloon dilatation of Eustachian tube combined with myringotomy and catheterization,” Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi, vol. 35, no. 12, pp. 1073–1077, 1084.
17.  S. Schroder, U. Reineke, M. Lehmann, J. Ebmeyer, and  Sudhoff, “Chronic obstructive eustachian tube dysfunction in adults: long-term results of balloon eustachian tuboplasty,” HNO, vol. 61, no. 2, pp. 142–151, 2013.
18. C. Zhang, C. Xu, F. Zheng et al., “the discussion on the application of simultaneous balloon Eustachian tuboplasty in the hearing reconstruction in patients with chronic suppurative otitis media,” Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi, vol. 34, no. 10, pp. 892–895, 2020.
19. C. Y. Hsieh, C. J. Chang, C. H. Sun et al., “Tympanoplasty with or without balloon eustachian tuboplasty for chronic suppurative otitis media with obstructive eustachian tube dysfunction,” Otology & Neurotology, vol. 41, no. 8, pp. 1077–1083, 2020.
20. L. Vaile, T. Williamson, A. Waddell, and G. Taylor, “Interventions for ear discharge associated with grommets (ventilation tubes),” Cochrane Database of Systematic Reviews, vol. 2, Article ID CD001933, 2006.
21. R. P. Venekamp, F. Javed, T. M. van Dongen, A. Waddell, and A. G. Schilder, “Interventions for children with ear discharge occurring at least two weeks following grommet (ventilation tube) insertion,” Cochrane Database of Systematic Reviews, vol. 11, Article ID CD011684, 2016.
22.  S. Y. Hwang, S. Kok, and J. Walton, “Balloon dilation for eustachian tube dysfunction: systematic review,” Journal of Laryngology & Otology, vol. 130, no. S4, pp. S2–S6, 2016.
23. H. Qin and J. Yang, “Efficacy of balloon Eustachian tuboplasty combined with grommet insertion in the treatment of chronic dilation Eustachian tube dysfunction,” Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi, vol. 32, no. 6, pp. 465–469, 2018.
24. R. Sheikh, H. Haidar, H. Abdulkarim et al., “Preoperative predictors in chronic suppurative otitis media for ossicular chain discontinuity: a cross-sectional study,” Audiology and Neurotology, vol. 21, no. 4, pp. 231–236, 2016.
25. N. S. Andresen, J. D. Sharon, C. L. Nieman, S. M. Seal, and B. K. Ward, “Predictive value of the Eustachian Tube Dysfunction Questionnaire-7 for identifying obstructive Eustachian tube dysfunction: a systematic review,” Laryngoscope Investigative Otolaryngology, vol. 6, no. 4, pp. 844–851, 2021.
26.  K. Mantsopoulos, V. *imsen, L. Taha et al., “Comparative analysis of titanium clip prostheses for partial ossiculoplasty,” American Journal of Otolaryngology, vol. 42, no. 5, Article ID 103062, 2021.
27. I. Baumann, B. Gerendas, P. K. Plinkert, and M. Praetorius, “General and disease-specific quality of life in patients with chronic suppurative otitis media—a prospective study,” Health and Quality of Life Outcomes, vol. 9, no. 1, p. 48, 2011
28. I. Kivekas, L. Poyhonen, A. Aarnisalo, M. Rautiainen, and D. Poe, “Eustachian tube mucosal inflammation scale validation based on digital video images,” Otology & Neurotology, vol. 36, no. 10, pp. 1748–1752, 2015.
29. M. C. Satmis and M. van der Torn, “Balloon dilatation of the Eustachian tube in adult patients with chronic dilatory tube dysfunction: a retrospective cohort study,” European Archives of Oto-Rhino-Laryngology, vol. 275, no. 2, pp. 395–400, 2018.
30.  R. Padia, J. A. Alt, K. Curtin et al., “Familial link of otitis media requiring tympanostomy tubes,” De Laryngoscope, vol. 127, no. 4, pp. 962–966, 2017.
31. C. M. Alper, M. S. Teixeira, T. J. Rath, D. Hall-Burton, and J. D. Swarts, “Change in eustachian tube function with balloon dilation in adults with ventilation tubes,” Otology & Neurotology, vol. 41, no. 4, pp. 482–488, 2020.
32. N. Ramakrishnan and P. Kadambi, “*e use of balloon eustachian tuboplasty in patients with eustachian tube dysfunction: a retrospective pilot usage experience,” Indian Journal of Otolaryngology and Head & Neck Surgery, vol. 72, no. 3, pp. 392–394, 2020.
33. H. Cheng, A. Saxby, N. Jufas, J. Kong, and N. Patel, “Balloon dilation eustachian tuboplasty for dilatory dysfunction: safety and efficacy analysis in an Australian cohort,” ANZ Journal of Surgery, vol. 91, no. 7-8, pp. 1480–1484, 2021.
34. Y. Q. Li, Y. B. Chen, G. D. Yin, and X. L. Zeng, “Effect of balloon dilation eustachian tuboplasty combined with tympanic tube insertion in the treatment of chronic recurrent secretory otitis media,” European Archives of Oto-RhinoLaryngology, vol. 276, no. 10, pp. 2715–2720, 2019.
35. L. Li, Y. Mao, N. Hu et al., “*e effect of balloon dilatation eustachian tuboplasty combined with grommet insertion on the structure and function of the eustachian tube in patients with refractory otitis media with effusion,” Annals of Palliative Medicine, vol. 10, no. 7, pp. 7662–7670, 2021.
36. Y. Zhang, J. Wang, Y. Wang, Q. Fu, and Y. Li, “Association between the air-bone gap and vibration of the tympanic membrane after myringoplasty,” Ear, Nose, & Droat Journal, vol. 100, no. 4, pp. 241–248, 2021.
37. S. Chen, M. Zhao, W. Zheng et al., “Myringotomy and tube insertion combined with balloon eustachian tuboplasty for the treatment of otitis media with effusion in children,” European Archives of Oto-Rhino-Laryngology, vol. 277, no. 5, pp. 1281– 1287, 2020.
38. C. F. Tai, K. Y. Ho, and K. H. Juan, “Age and the prognosis of tympanoplasty type I,” De Kaohsiung Journal of Medical Sciences, vol. 14, no. 9, pp. 542–547, 1998.
39. Y. Si, Y. Chen, G. Xu, X. Chen, W. He, and Z. Zhang, “Cartilage tympanoplasty combined with eustachian tube balloon dilatation in the treatment of adhesive otitis media,” De Laryngoscope, vol. 129, no. 6, pp. 1462–1467, 2019.

40. S. Teixeira, J. D. Swarts, and C. M. Alper, “Accuracy of the ETDQ-7 for identifying persons with eustachian tube dysfunction,” Otolaryngology—Head and Neck Surgery, vol. 158, no. 1, pp. 83–89, 2018.