Enhanced Eustachian Tube Function and Hearing Recovery with Combined Balloon Dilatation and Tympanic Membrane Catheterization in Secretory Otitis Media

Introduction

A non-suppurative inflammatory condition of the middle ear, secretory otitis media (SOM), also known as otitis media with effusion, can occur in children and adults [1]. According to recent epidemiological data, the prevalence in adults is estimated at 2% to 4%, with a higher incidence in individuals with allergic rhinitis, chronic sinusitis, or structural nasal abnormalities [2]. SOM leads to substantial morbidity, impairing communication, work performance, and social interaction. Obstruction of the eustachian tube (ET) reduces surfactant secretion in the middle ear cavity, resulting in increased ET pressure and negative middle ear pressure. Simultaneously, mucosal cells of the middle ear exude interstitial fluid, causing effusion and hearing loss, often accompanied by ear pain and tinnitus [3,4]. The etiology of SOM in adults includes ET dysfunction, nasal infection, and immune response; if left untreated, it can progress to adhesive otitis media, cholesteatoma, or cholesterol granuloma [5,6]. Currently, medical therapy – including the use of glucocorticoids, antibiotics, antihistamines, mucolytics, and decongestants – is aimed at reducing inflammation and promoting drainage. However, prolonged treatment, limited efficacy, and antibiotic resistance remain challenges [7,8]. Intratympanic ambroxol hydrochloride can dissolve viscous secretions and improve surfactant synthesis, but its long-term benefits are limited. When conservative therapy fails, surgical options such as eustachian tube balloon dilatation (ETBD) and tympanic membrane catheterization (TMC) are considered [9,10]. ETBD uses a balloon catheter to dilate the cartilaginous portion of the ET under endoscopic guidance, improving ventilation and drainage [11,12]. TMC involves insertion of a ventilation tube through the tympanic membrane to equalize pressure and clear middle ear fluid [13]. Treating SOM therefore requires addressing both the underlying ET dysfunction and the middle ear effusion.

Several evaluation systems are used in SOM research: the eustachian tube manometry R score and the Eustachian Tube Score (ETS) for functional assessment; the Eustachian Tube Dysfunction Questionnaire-7 (ETDQ-7), a validated 7-item patient-reported tool for symptom severity; pure-tone audiometry for hearing thresholds; and inflammatory biomarkers such as procalcitonin (PCT), high-sensitivity C-reactive protein (hs-CRP), and interleukin-6 (IL-6), which reflect local and systemic inflammation [14–17]. Clinical studies support the individual benefits of ETBD and TMC [18,19]. However, while meta-analyses have shown that tympanostomy tubes reduce effusion and improve hearing, complications, such as persistent perforation are possible [20,21], and recurrence after ETBD alone remains common [22,23]. Evidence regarding the combined use of ETBD and TMC in adults is scarce, and whether a synergistic effect exists remains unclear. Therefore, this study aimed to compare outcomes of ETBD alone versus ETBD combined with TMC in 90 adult patients with SOM. We hypothesized that the combined approach would result in superior clinical efficacy, greater improvement in ET function, lower inflammation, and reduced recurrence, compared with ETBD alone.

Material and Methods

ETHICS STATEMENT:

This study was designed as a prospective comparative study and was conducted in accordance with the principles of the Declaration of Helsinki. The study protocol was reviewed and approved by the Medical Ethics Committee of our hospital (approval No. ZQKJYY-IRB-2025-001). Written informed consent was obtained from all participants prior to enrollment, after providing them with a detailed explanation of the study objectives, procedures, potential risks, and benefits. All data were anonymized to protect patient confidentiality.

GENERAL INFORMATION:

Between September 2020 and September 2022, a total of 90 patients (110 ears) who received a diagnosis of SOM and treatment at our hospital were randomly assigned to 2 groups, each including 45 patients (55 ears). The balloon-only group underwent simple ETBD, while the balloon plus catheterization group received TMC in addition to ETBD. In the balloon-only group, there were 22 men and 23 women, with an age range of 23 to 68 years (mean age: 37.81±1.59 years). The duration of illness varied from 6 to 36 months, with an average duration of 22.29±2.11 months. Similarly, the balloon plus catheterization group included 21 men and 24 women, with an age range of 23 to 69 years (mean age: 37.84±1.61 years). The duration of illness ranged from 6 to 36 months, with an average duration of 22.31±0.13 months. No statistically significant differences were found in the baseline characteristics between the 2 groups (P>0.05). The diagnosis of SOM was based on the Clinical Practice Guideline: Secretory Otitis Media (Updated) [24], which includes the absence of acute middle ear infection on rigid ear endoscopy, effusion in the tympanic chamber, a disease duration exceeding 3 months, failure of conservative treatment, an acoustic impedance test showing type B and C curves, and a pure-tone hearing threshold test indicating conductive hearing loss. The flow chart of the study is presented in Figure 1.

INCLUSION AND EXCLUSION CRITERIA:

Inclusion criteria required all patients to exhibit symptoms of adult SOM, including tinnitus and ear tightness, persisting for more than 3 months despite standard conservative treatment. Patients with conductive or mixed deafness, in which the bone-air conduction difference was between 15 dB and 40 dB, were included. Otoscopic examination had to reveal an intact, pale yellow tympanic membrane with signs of exudation and fluid accumulation. All patients provided written informed consent. Patients were required to be aged 18 to 70 years and capable of completing all follow-up visits. The exclusion criteria included middle ear lesions, ET malformations, and space-occupying lesions confirmed by temporal bone computed tomography (CT). Patients with nasopharyngeal carcinoma or nasal pathologies detected via flexible or rigid electronic nasopharyngoscopy, as well as those with nasal septum deviation or ET atresia, were excluded. Additionally, individuals with acute upper respiratory tract infections, recurrent nasal polyps with allergic rhinitis, or abnormal liver, kidney, and coagulation function were not considered for surgery. Other exclusions included congenital cleft lip and palate cases unsuitable for immediate surgery, patients unable to tolerate general anesthesia, individuals under 18 years old, and those with mental illness or cognitive impairment. Patients who missed follow-up visits or had incomplete data were excluded from final analysis.

SAMPLE SIZE:

The sample size (n₁) was calculated as per the following formula:

The sample size was calculated based on a bilateral α of 0.05 and a β of 0.20. Based on previous literature, using the total effective rate as the effect index and setting P1=0.96 and P2=0.77, calculations indicated a requirement of 41 patients per group. Considering a 10% attrition rate, the study included 45 patients per group, totaling 90 patients.

EUSTACHIAN TUBE BALLOON DILATATION:

Patients in the balloon-only group underwent simple balloon dilatation of the ET. After decongestion of the nasal mucosa with a 0.1% lidocaine and epinephrine pledget (Jiangsu Hansoh Pharmaceutical Co, Ltd, Lianyungang, China) placed with gun-shaped forceps, the Manxiang ETBD system (Manxiang Medical Technology Co, Ltd, Hangzhou, China) was assembled and connected to a pressurized pump prefilled with 8 to 10 mL of sterile saline. Under endoscopic guidance (Karl Storz, Tuttlingen, Germany), the pharyngeal opening of the ET was identified, and a balloon catheter was carefully introduced. Pressure was gradually increased to 10 ATM and maintained for 2 min. If misalignment or bending occurred, the catheter was adjusted. The balloon was then retracted slightly and re-inflated for another 2 min before removal. This process dilated the cartilaginous portion of the ET and promoted restoration of ciliary function. All procedures were performed by surgeons with more than 5 years of experience in endoscopic otologic surgery.

TMC COMBINED WITH ETBD:

In the balloon plus catheterization group, patients received ETBD in combination with TMC. Under general anesthesia, the surgical field was disinfected, and an anterior-inferior tympanic membrane incision was made using a microscope or Karl Storz ear endoscope. Middle ear fluid was aspirated before placement of a tympanic ventilation tube (Medtronic Xomed, Jacksonville, FL, USA) to facilitate aeration and drainage. The nasal cavity was again prepared with lidocaine and epinephrine pledgets, and the ETBD procedure was performed as described above, including balloon inflation to 10 ATM for 2 min, release of negative pressure for 30 s, and repetition of the inflation cycle. Following the intervention, the instrument set was removed.

POSTOPERATIVE CARE:

The patients in both groups received prophylactic intravenous cefuroxime (1.5 g every 12 h, GlaxoSmithKline, Brentford, UK) for 3 days. Compliance and recovery were monitored by weekly follow-up phone calls and scheduled outpatient clinic visits.

CLINICAL EFFICACY:

Clinical efficacy was evaluated at 6 months after treatment. Patients were classified into 3 categories: (1) Recovery – complete resolution of symptoms, normal hearing on audiometry, and no recurrence of effusion; (2) Improvement – partial relief of symptoms with reduced or absent middle ear effusion and no recurrence; and (3) No change – persistence of symptoms, unresolved middle ear effusion, or recurrence. The total effective rate was calculated using the following formula:

ET FUNCTION:

ET function was assessed using manometry (Zhejiang Orient Medical Instrument Co, Ltd, Wenzhou, China) at baseline and 6 months after treatment. Manometry measured the R value, which reflects ET patency by recording the pressure change during a swallowing maneuver at 3 preset pressure levels (30, 40, and 50 mbar). A higher R value indicated improved ET opening and pressure regulation ability.

STATISTICAL ANALYSIS:

Data were analyzed using SPSS software version 21.0 (IBM Corp, Armonk, NY, USA). Continuous variables with a normal or approximately normal distribution were expressed as mean±standard deviation. Paired t tests were used for intra-group comparisons, while independent-sample t tests were used for inter-group comparisons. Categorical data were represented as n (%) and analyzed using the chi-square test. All tests were 2-tailed, and a P value <0.05 was considered statistically significant. Missing data were handled using the last observation carried forward method. Analyses were performed on an intention-to-treat basis.

Results

THERAPEUTIC EFFECTS:

The therapeutic efficacy of the treatments was assessed after 6 months. In the balloon plus catheterization group (n=45), 34 patients (75.56%) achieved complete recovery, 14 patients (31.33%) showed improvement, and only 2 patients (4.44%) minimal or no change, resulting in a total effective rate of 95.56%. In contrast, in the balloon-only group (n=45) 22 patients (48.89%) achieved complete recovery, 13 patients (28.89%) showed improvement, and 10 patients (22.22%) had minimal or no change, leading to a total effective rate of 77.78% (χ2=6.154, P<0.05). These data are summarized in Table 1 (table created using SPSS software version 21.0, IBM Corp, Armonk, NY, USA). These results indicate that adding TMC to ETBD significantly improved treatment outcomes, compared with ETBD alone.

R VALUE OF ET MANOMETRY BEFORE AND AFTER TREATMENT:

No significant difference was found in the R values of ET manometry between the 2 groups before treatment (P>0.05). However, after 6 months of treatment, both groups exhibited increased R values. The balloon plus catheterization group demonstrated a significantly greater improvement in R scores at 30, 40, and 50 mbar, compared with the balloon-only group (all P<0.05). This suggests that the combined intervention resulted in superior recovery of ET function. Detailed results are provided in Table 2.

SERUM PCT, HS-CRP, AND IL-6 LEVELS BEFORE AND AFTER TREATMENT:

Before treatment, there were no significant differences in serum PCT (μg/L), hs-CRP (mg/L), and IL-6 (pg/mL) levels between the 2 groups (P>0.05). After 6 months, all 3 inflammatory markers were significantly lower in the balloon plus catheterization group than in the balloon-only group (all P<0.05). This indicates that the combined therapy more effectively reduced inflammation associated with SOM. Results are shown in Table 3.

ETDQ-7 SCALE SCORE AND ETS SCORE BEFORE AND AFTER TREATMENT:

Before treatment, there were no significant differences in the ETDQ-7 and ETS scores between the 2 groups (P>0.05). However, after 6 months of treatment, the balloon plus catheterization group showed a greater reduction in ETDQ-7 scores and a greater improvement in ETS scores, compared with the balloon-only group (both P<0.05), as shown in Table 4.

PURE-TONE HEARING THRESHOLDS BEFORE AND AFTER TREATMENT:

Before treatment, there was no significant difference in pure-tone hearing thresholds (dB HL) between the 2 groups (P>0.05). After 6 months, both groups experienced significant reductions in pure-tone hearing thresholds, but the balloon plus catheterization group exhibited a significantly greater improvement (P<0.05). This indicates that adding TMC enhanced recovery of auditory function. Figure 2 illustrates these results.

INCIDENCE OF COMPLICATIONS AND RECURRENCE RATE AFTER 6 MONTHS:

The incidence of complications was low in both groups. In the balloon plus catheterization group, there was 1 case each of ET pharyngeal mouth adhesion, mucosal tear of the eustachian tube, and middle ear hemorrhage, with a total complication rate of 6.66%. In the balloon-only group, there was 1 case each of ET pharyngeal mouth adhesion and mucosal tear, and 2 cases of middle ear hemorrhage, leading to a total complication rate of 8.88% (P>0.05). While there was no significant difference in complication rates, the recurrence rate was significantly lower in the balloon plus catheterization group (4.44% vs 22.22%, χ2=6.154, P<0.05) after 6 months of follow-up. This suggests that the combination therapy not only improved initial outcomes but also reduced long-term recurrence of SOM. These findings are summarized in Table 5.

Discussion

In this study, we compared the clinical outcomes of ETBD alone (balloon-only group) with those of ETBD combined with tympanic TMC (balloon plus catheterization group) in adult patients with SOM. Our main findings showed that the combined approach achieved a higher total effective rate (95.56% vs 77.78%), greater improvement in ET function scores (R value and ETS), more significant reduction in ETDQ-7 symptom scores, better hearing recovery, and lower recurrence rates after 6 months, without increasing complication rates. SOM is a common otologic disorder among adults, often resulting in hearing loss and tympanic membrane complications if left untreated [25,26]. Chronic negative pressure in the tympanic cavity leads to tympanic membrane retraction and, in severe cases, cholesteatoma formation [27,28]. ETD is recognized as the main pathophysiological mechanism, impairing middle ear ventilation and drainage due to mucosal inflammation, anatomical obstruction, or infection [29]. Studies have shown pharyngeal edema and decreased wall mobility in many ETD cases, highlighting the role of structural and inflammatory changes [30,31]. Nasal pathologies, such as septal deviation and sinusitis, are also linked to ETD. Kaya et al and Maniakas et al demonstrated improved ET function after corrective nasal surgery, reinforcing the anatomical and functional connection between the upper airway and middle ear ventilation [32,33]. ETBD, introduced by Ockermann et al [34], has become a widely adopted technique that improves tubal patency and middle ear ventilation, with reported benefits in adult SOM [35]. However, recurrence still occurs, particularly in patients with persistent mucosal inflammation or impaired pressure receptor function. Reported complications include tympanic membrane perforation and submucosal emphysema, although the overall incidence is low (approximately 1.7%) [36,37]. TMC offers an additional strategy by facilitating middle ear fluid drainage and equalizing pressure [38,39]. While tympanostomy tubes are a conventional choice, meta-analyses have reported possible long-term sequelae, such as otorrhea, tympanosclerosis, and persistent perforation [20,21]. TMC can offer a less invasive and tissue-preserving alternative.

The rationale for combining ETBD and TMC is to address both the underlying cause (ETD) and the accumulated middle ear effusion. This dual approach has the potential to improve immediate and long-term outcomes. Wu et al also proposed evaluating balloon dilation with tympanostomy tube insertion, supporting the concept of combined therapy for superior results [19].

In the present study, in addition to evaluating clinical and functional outcomes, we evaluated inflammatory biomarkers, including PCT, hs-CRP, and IL-6, which are relevant to the pathophysiology of SOM. PCT is a sensitive marker of bacterial inflammation and systemic infection, and elevated levels in SOM can reflect secondary bacterial activity within the effusion [40]. The inflammatory biomarker hs-CRP is a widely used acute-phase protein that indicates systemic inflammatory status and correlates with mucosal edema and effusion formation in otitis media [16]. IL-6 is a pro-inflammatory cytokine released by middle ear epithelial and immune cells in response to infection or chronic inflammation. Elevated IL-6 levels have been demonstrated in middle ear effusions and contribute to persistent fluid accumulation and mucosal pathology [17]. Collectively, these biomarkers provide objective evidence of the inflammatory burden in SOM and allow evaluation of the anti-inflammatory effect of interventions.

In the present study, our combined group achieved better clinical efficacy and functional recovery than did the ETBD-alone group, consistent with the results of Yin et al and Dai et al, who also reported that adjunctive interventions can enhance outcomes after ETBD [22,41]. Our biomarker results, showing greater reductions in PCT, hs-CRP, and IL-6 after ETBD combined with TMC, suggest that the combined approach not only improves mechanical ventilation of the middle ear but also more effectively suppresses inflammatory processes. This finding aligns with that of Xu and Yan [42], who demonstrated enhanced anti-inflammatory effects when balloon dilation was coupled with adjunctive therapy in SOM. The strengths of our study include the randomized design, use of objective and subjective outcome measures, and evaluation of inflammatory biomarkers alongside functional and audiometric endpoints.

However, several limitations must be acknowledged. First, the sample size was small, which can limit the generalizability of our findings. Second, the follow-up period was limited to 6 months; therefore, the durability of benefits and long-term recurrence rates remain unknown. Third, the absence of blinding could have introduced performance or detection bias. Fourth, operator variability in performing endoscopic procedures may have influenced results. Fifth, certain methods have inherent limitations – ETDQ-7 is a subjective tool susceptible to patient perception, R value measurements can be influenced by patient effort, and inflammatory marker levels can fluctuate due to systemic factors unrelated to SOM. Future research should involve multicenter, randomized controlled trials with larger sample sizes and longer follow-up, standardization of surgical technique, and comparative evaluations against other therapeutic modalities, such as tympanostomy tubes, systemic corticosteroids, or newer minimally invasive procedures.

Conclusions

This comparative study showed that ETBD combined with TMC provided superior clinical outcomes than did ETBD alone in adult patients with SOM (otitis media with effusion). The combined approach significantly improved ET function, reduced inflammatory marker levels, enhanced hearing recovery, and lowered recurrence rates without increasing complication rates. While promising, the findings are limited by the small sample size, short follow-up period, lack of blinding, and possible operator variability. Future multicenter, randomized controlled trials with larger sample sizes and extended follow-up are needed to confirm these results and inform clinical practice guidelines.