|Year : 2022 | Volume
| Issue : 4 | Page : 282-287
Managing eustachian tube dysfunction with balloon catheterization: A local experience report
ST Tan1, Noor Dina Hashim2, Asma Abdullah2
1 Department of Otorhinolaryngology-Head and Neck Surgery, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Bandar Tun Razak, Kuala Lumpur; Department of Otorhinolaryngology-Head and Neck Surgery, Hospital Kemaman, Jalan Da'Omar, Chukai, Terengganu, Malaysia
2 Department of Otorhinolaryngology-Head and Neck Surgery, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Bandar Tun Razak, Kuala Lumpur, Malaysia
|Date of Submission||14-Feb-2022|
|Date of Decision||06-Mar-2022|
|Date of Acceptance||25-Mar-2022|
|Date of Web Publication||29-Dec-2022|
Prof. Noor Dina Hashim
Department of Otorhinolaryngology-Head and Neck Surgery, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaacob Latif, Bandar Tun Razak, Kuala Lumpur
Source of Support: None, Conflict of Interest: None
Objective: Eustachian tube dysfunction (ETD) is not commonly acknowledged until it leads to sequelae within the middle ear. Thus, treatments are focusing on treating active middle ear diseases repetitively rather than identifying possible fundamental causes. This study aims to report a preliminary local experience in treating ETD using balloon dilatation. Methods: This prospective, randomized controlled study was conducted in a tertiary academic center. Sixteen patients who were identified with symptoms of ETD were recruited. Six who had failed initial medical therapy underwent balloon dilatation of Eustachian tube (BDET); meanwhile, ten subjects were recruited into the medical treatment group. The primary efficacy endpoint was the comparison of reduction from baseline in overall 7-item Eustachian Tube Dysfunction Questionnaire (ETDQ-7) score. Added endpoints were normalization of tympanogram and improvement of tympanic membrane appearance at 2 weeks, 6 weeks, and 3 months after intervention. Results: The median in reduction of overall ETDQ-7 score for the interventional group was 2.93 (2.14, 3.14) versus 0.43 (0, 0.86) for the control group. Reduction in overall ETDQ-7 score showed a significant improvement at 6 weeks which was persistent at 3 months post balloon dilatation (P < 0.05). Similarly, the BDET group demonstrated changes in tympanogram at 6 weeks and 3 months post balloon dilatation (P < 0.05). Tympanic membrane appearances were similar at the end of the study in both the groups. Conclusion: BDET is a promising precise treatment for patients who present with symptoms of ETD. The improvement of symptoms it provides may increase the readiness for it to be introduced as a standard practice in local settings and beyond.
Keywords: Balloon dilatation, Eustachian tube, Eustachian tube dysfunction, otitis media
|How to cite this article:|
Tan S T, Hashim ND, Abdullah A. Managing eustachian tube dysfunction with balloon catheterization: A local experience report. Indian J Otol 2022;28:282-7
| Introduction|| |
Eustachian tube dysfunction (ETD) is a disorder in which the Eustachian tube (ET) fails to equalize pressure between the middle ear and the atmosphere and other functions include secretion clearance and protection of the middle ear from nasopharyngeal secretion reflux. It is a disease spectrum that can be broadly classified from obstructive to patulous dysfunction. ETD symptoms may go unnoticed or underappreciated until they cause pronounced symptoms as a result of active middle ear diseases or complications.
The prevalence of obstructive ETD in adult populations has been estimated to range from 0.9% to 5%., Symptoms of obstructive ETD are primarily caused by a failure of the functional valve to open or a narrowing of the tube lumen, resulting in aural fullness, otalgia, tinnitus, and hearing loss. In patulous ETD, on the other hand, the functional valve is pathologically patent, causing the tube to remain intermittently open instead of closed causing autophony and tinnitus.
Medical therapy and the insertion of a ventilation tube to equalize middle ear pressure and treat infections are common symptomatic treatments for obstructive ETD and its middle ear sequelae. Conventional practice of using nasal corticosteroid therapy had limited efficacy as the etiology of ETD itself remains unclear. The insertion of a ventilation tube into the tympanic membrane may provide temporary symptom relief. It does not, however, address the underlying pathology and may result in additional complications such as persistent ear discharge, permanent tympanic membrane perforation, and cholesteatoma formation. These traditional methods are widely practiced in our local settings, as middle ear presentations are increasingly being complained about and acknowledged at initial visits than ETD symptoms. Even though most patients experienced improvement or resolution of their middle ear symptoms, some continue to experience recurrent symptoms or disease progression. These confluences of conditions are frequently observed years after initial treatments, possibly as a result of unrecognized ETD symptoms.
The effectiveness and safety profile of balloon dilatation in endoscopic sinus surgery has contributed to its use in treating obstructive ETD. This is the most recent modality in treating the primary pathological site by crushing the inflamed mucosa and submucosa layers causing lymphoid hyperplasia within the cartilaginous ET lumen. Healing of this injury by thinner fibrous scar results in the formation of a new lining of healthy mucosa which may improve ETD symptoms., Previous cadaveric and clinical studies have shown that balloon dilatation of the ET (BDET) is safe, feasible, and effective.
This increasing universal understanding and acceptance of ETD and BDET have augmented our intention to initiate this preliminary randomized controlled trial to introduce the use of balloon dilatation in local settings, as well as to determine its effectiveness in treating ETD.
| Methods|| |
This prospective, randomized controlled study was conducted in a tertiary academic center from June 1, 2019, to August 31, 2020, to observe the effectiveness of balloon dilatation in treating patients with ETD compared to the medical treatments commonly practiced in our center. The institutional ethical committee has approved the study with the project code of FF-2019-291. Written consent was obtained from the patients.
Adult patients aged 18 and above with moderate-to-severe ETD symptoms based on ETDQ-7 scoring and Type B or C tympanogram were recruited. Patients with a history or evidence of acute upper respiratory tract infection including sinusitis and acute otitis media, active ear disease, adenoid hypertrophy, cleft palate or history of cleft palate repair, craniofacial abnormality, cystic fibrosis, ciliary dysmotility syndrome, Down syndrome, systemic immunodeficiency, and postradiotherapy were excluded.
Consented patients were allocated into balloon dilatation and medical treatment groups using Random Allocation Software Version 1.0. (Mahmood Saghaei, Department of Anaesthesia, Isfahan University of Medical Sciences, Isfahan, Iran). The randomization scheme is hidden from treating physicians and patients. There is no masking of interventions after randomization. Patients in the medical treatment group were given intranasal steroids, whereas subjects in the intervention group were scheduled for an elective ET balloon dilatation procedure. All patients were reassessed at 2-week, 6-week, and 3-month intervals using the same pretreatment tools.
The BDET was performed transnasally by using XprESS ENT dilation system under general anesthesia with endoscopic guidance. The hypotube was bent 45° at 2 cm marked from the tip to ensure safety and correct placement within the cartilaginous portion of the ET. Subsequently, it was inserted via nostril into the ET opening, inflated for 2 min, at 12 atm, and deflated before removing. A preintervention nasoendoscopy was performed to identify any anatomical obstruction.
7-item Eustachian Tube Dysfunction Questionnaire
The 7-item ET Dysfunction Questionnaire (ETDQ-7) is a validated, disease-specific questionnaire to evaluate the severity of ETD symptoms. The overall ETDQ-7 score will determine the severity category of the symptoms: 1–2 “no symptom” category, 3–5 “moderate symptom” category, and 6–7 “severe symptom” category. The total scores were divided by 7 to get an overall ETDQ-7 score. A higher overall score indicates more severe ETD symptoms. The differences in overall scores between pre- and posttreatment of each group were used to report the study's primary outcome.
Tympanic membrane appearance
Baseline tympanic membrane appearance was documented as normal or retracted based on Sade grading of pars tensa retraction. Improvement at follow-up is defined as a change of tympanic membrane appearance from retracted to normal, or improvement of tympanic membrane retraction.
Tympanometry assessments at baseline, 2 weeks, 6 weeks, and 3 months post treatment were documented. Improvement of tympanometry is defined as a change from Type B at baseline to Type A, or Type C at baseline to Type A post treatment.
The primary endpoint of the study is the median change of overall ETDQ-7 score from baseline, at the interval of 2 weeks, 6 weeks, and 3 months post treatment, comparing between the balloon dilatation and medical treatment groups. Tympanic membrane appearance and tympanometry results were secondary endpoints assessed during interval visits.
Sample size and statistical analysis
The sample size was calculated using software PS: Power and Sample Size Calculation version 3.1.2 2014. SPSS version 22.0 (IBM, Armonk, NY) was used for data analysis. Descriptive analysis was carried out to describe the background characteristics of the study subjects. All categorical data were expressed in percentage, while numerical data were described in the median and interquartile range as the data collected were nonnormally distributed. Mann–Whitney U-test was used to compare symptom improvement (overall ETDQ-7 scores) and Fisher's exact test was used to compare the proportion of improvement of tympanic membrane appearance and tympanogram between the two groups.
| Results|| |
Sixteen patients (male, n = 7, female, n = 9) who fulfilled the inclusion criteria were enrolled. An initial response to the ETDQ-7 was recorded from all patients. Six patients were randomized into balloon dilatation group and ten allocated into medical treatment group. The mean age of recruited patients was 56.3 (±15.8). There was no significant gender predilection in this cohort. The most common symptoms that were reported include aural fullness (100%), ear pain (87.5%), hearing loss (87.5%), and tinnitus (56.3%), whereas symptoms such as rhinorrhea, nasal blockage, ear discharge, and vertigo were uncommon. No statistically significant difference of symptoms was observed between the groups.
The baseline median ETDQ7 score was 4.21 in the balloon dilatation group and 4.57 in the medical treatment group. This suggested that the patients in both the groups had similar moderate severity of symptoms. The overall ETDQ-7 score for the balloon dilatation group showed improvement at 2 weeks (3.14), 6 weeks (2.57), and 3 months (1.79) post treatment. These reducing scores suggested that patients in the balloon dilatation group had achieved symptomatic improvement from “moderate symptom” category to “no symptom” category. Meanwhile, patients in the medical treatment group remained in the “moderate symptom” category within the same interval of assessments with a median score of 3.86, 3.79, and 3.93, respectively [Figure 1].
|Figure 1: 7-item Eustachian Tube Dysfunction Questionnaire score between medical treatment group and balloon dilatation group at different time points|
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Comparison of the median reduction in overall ETDQ-7 score at each interval was also analyzed to evaluate the onset of improvement after each treatment. At 2 weeks, the median reduction of score in the balloon dilatation group was 1.57 (0.43, 1.86) while the medical group recorded 0.29 (0, 0.43). Further reduction of score was observed at 6 weeks, 2.21 (1.57, 2.71) and 0.36 (0, 0.57) in the balloon dilatation group and the medical group, respectively. The median reduction in ETDQ-7 score is statistically significant for the balloon dilatation group as early as 6 weeks (P = 0.007, < 0.05) which remained significant up to 3 months post treatment [Table 1].
|Table 1: Reduction of overall Eustachian Tube Dysfunction Questionnaire-7 score post treatment|
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As for tympanometry assessment, one patient from each group showed improvement in the left ear as early as 2 weeks. At 6-week intervals, a total of three patients from the balloon dilatation group exhibited improvement which was sustained until 6 months post intervention. However, no improvement was observed in any of the patients in the medical treatment group at the end of the study. For the right ear, timely changes on tympanogram were observed in two patients from the balloon dilatation group at 2 weeks, three patients at 6 weeks, and four patients at 3 months. Meanwhile, similar to the left ear observation in the medical treatment group, there was no tympanogram improvement manifested by any patients during three separate intervals of assessments. Overall, the differences of improvement in tympanometry are statistically significant (P = 0.036, < 0.05) as early as 6 weeks post balloon dilation and maintained at 3-month (P = 0.008, < 0.05) review [Table 2].
We also examined the tympanic membrane appearance of the individual ear of all patients in both the groups. There were two of four patients in the balloon dilatation group who showed change of the tympanic membrane appearance in both ears at 3 months post treatment. Otherwise, in the medical treatment group, none showed any difference. This outcome did not reach statistical significance (P = 0.125) [Supplement Table 1].
| Discussion|| |
When the ET fails to adequately equalize pressure between the middle ear and the nasopharynx, this is referred to as ETD. The precise mechanisms of ETD are complex and remain unknown. ETD is postulated to occur when the mucosa of the tube becomes inflamed as a result of an infectious or inflammatory condition, such as rhinitis, rhinosinusitis, or upper respiratory tract infection, causing difficulties with pressure equalization. Long-term ETD has long been associated with otitis media with effusion, middle ear atelectasis, and chronic otitis media.
To be diagnosed with ETD, patients must exhibit symptoms of pressure disequilibrium in the affected ear, specifically aural fullness, popping, or otalgia, according to Schilder et al. These symptoms may be recurring. All patients recruited in this cohort complained of aural fullness, and 87.5% also had otalgia and hearing loss. Similarly, Meyer et al. conducted a randomized controlled trial and found that aural fullness and hearing loss were the two most common symptoms among patients, with only 70% reporting otalgia. This group recruited people with ETD for more than a year, which could explain the tolerance to pain and changes in perception into aural fullness rather than otalgia.
Most clinicians do not immediately recognize the primary symptoms of ETD as the complaints are more attributed to its sequelae, including the more common secretory otitis media. The conservative treatments may appear to resolve active symptoms, but despite good compliance, the underlying ETD issue may later cause recurrent complaints. Worse, it may lead to irreversible negative middle ear pressure consequences, including retracted tympanic membrane or cholesteatoma. This practice is similarly observed in our center, most probably attributed to a lack of exposure to the significance of ETD and the importance of addressing it before it progresses to its sequel. The surge of more studies about ETD and middle ear ventilation, as well as successful alternative treatments such as BDET, in recent years is an eye-opener that is worth investing in.
The burden of ETD is seldom reported, possibly due to limited reliable clinical assessments before the ETDQ-7 was recognized widely. A growing interest in ETD has also brought attention to the potential secondary effects such as situational avoidance, communication difficulties, and reduced productivity. Mccoul and Anand have developed a disease-specific ETDQ-7 to aid in assessing the severity of the ETD, replacing traditional subjective assessment of ETD symptoms.
At the time of the baseline assessment, both the groups of subjects in this cohort reported “moderate symptoms.” After 3 months of treatment, the self-assessment reports in the medical treatment group remained unchanged, whereas those with balloon dilatation experienced a significant reduction in overall ETDQ-7 score as early as 6 weeks. At the end of the study, these patients reported a consistent improvement of symptoms. During the same postoperative day, two patients reported immediate relief of aural fullness and otalgia. This could imply that some patients may experience subjective symptomatic improvement on the same day as the procedure. Our results are congruent with an earlier observation by Meyer et al., who reported significant overall ETDQ-7 score improvement from 4.6 to 1.7 (no symptom) in just 6 weeks post treatment.
Homogeneously, several recent studies had achieved the same results in 6 weeks after balloon dilatation., Our subjects' baseline overall ETDQ-7 scores were nearly identical to those in the preceding studies (moderate symptoms); however, the majority of them in this relatively small sample size cohort reached the “no symptom” category in ETDQ-7 assessment only after 3 months of treatment.
Patients randomized to the medical treatment group, on the other hand, reported only minor improvement after treatment, which was statistically insignificant. They remained in the same symptom category they were in prior to treatment. This finding is consistent with the findings of Meyer et al., who found that after 6 weeks of medical treatment, the patients remained in the “moderate symptom” group. When compared to the balloon dilatation group, symptom improvement in the medical treatment group was inconsistent. The patient reported gradual symptom improvement beginning at 6 weeks and lasting up to 3 months. Despite the fact that the majority of studies had concluded that balloon dilatation is superior to medical treatment, some patients may benefit from medical treatment.,, The British Society of Allergy and Clinical Immunology has proposed guidelines for managing allergic and nonallergic rhinitis, which concluded that apparent clinical improvement may not be achieved until 2 weeks after correct technique administration of intranasal steroids in a fully compliant patient. This finding could explain the symptom's inconsistent and delayed progression, resulting in a longer follow-up period.
These findings suggest that patients who underwent balloon dilatation may have noticeable relief of symptoms sooner than those who received conventional medical treatment. This promising result could pave the way for clinicians at our center and elsewhere to adopt a balloon dilatation procedure for ETD, allowing for a larger cohort to be studied. This observation should not be dismissed because continuous longitudinal data on ETDQ-7 improvement are needed to conclude a definitive intervention for ET dysfunction. This simple and effective procedure has the potential to lower health-care costs while improving patients' quality of life.
Sade classification was used to grade the pars tensa of tympanic membrane retraction. The gain of tympanic membrane appearance was defined by the improvement of the Sade grading. Two patients in the balloon dilatation group had complete resolution of retraction 3 months after baseline appearance. This clinically significant progression occurred infrequently, as 33.3% of patients in the balloon dilatation group improved 3 months after the intervention. In the medical treatment group, however, none were noticed. Poe et al. had found a significant improvement in the appearance of the tympanic membrane in 45.5% of patients who underwent the same procedure at 6-month review.
We hypothesized that patients who had ET balloon dilatation but did not have chronic ear infections would have improved tympanic membrane appearance. A natural history of chronically retracted tympanic membrane, on the other hand, suggested that it may remain stable or improve over time. Ideally, by polishing up the function of the ET, the ventilation of the middle ear will eventually get better. Hence, it is recommended to schedule a long-term follow-up to assess the improvement in the appearance of the tympanic membrane. If the exact timeline is considered, this finding suggests a notable limitation in having a subjective clinical evaluation of the tympanic membrane compared to the objective ETDQ-7 assessment to distinguish treatment improvement in ET dysfunction.
In terms of objective assessment using tympanometry, 12 ETs (six patients) underwent balloon dilatation in this study, and 58.3% of ETs documented improvement in their tympanogram with significant reduction of the overall ETDQ-7 scores, with one patient as early as 2 weeks. This encouraging finding persisted throughout the study. Williams et al., in their recent article regarding tympanometric outcome analysis among patients who underwent BDET, also demonstrated a statistically significant improvement with 36% of ears having improvement in tympanogram type between 3 and 15 months of follow-up. We believe that with balloon dilatation, the ET function will be restored over time; therefore, a tympanogram should be performed on a regular basis to monitor progress.
The emerging minimally invasive endoscopic-assisted ET balloon dilatation with a favorable safety profile has gradually supplanted previously reported surgical interventions such as bougie dilatation, bony ET, middle ear shunting, and laser tuboplasty. Nonetheless, due to a lack of standardized outcome measures, the long-term benefits of balloon dilatation have yet to be established. Kujawski and Poe evaluated the outcome of laser Eustachian tuboplasty by measuring the tympanic membrane atelectasis and impedance tympanometry. Sedlmaier et al. reported the improvement of middle ear ventilation after laser tuboplasty by the ability to perform Valsalva maneuver and assessment of tympanogram changes. However, neither study quantified the severity of the symptoms, which impacts are important on quality of life. Ideally, the outcome measures should include both subjective and objective measures. Smith et al. proposed the combination of patient-reported outcome measure and objective tympanometric test including tympanometry, sonotubometry, or tubomanometry in order to accurately assess the outcome. A systematic review by Huisman et al. consisting of retrospective case series and prospective case series concluded that while the current literature supports the use of balloon dilatation in treating ETD, placebo-controlled trials were necessary. Although there was heterogeneity in the indications, balloon devices, protocols, and outcome measures, the results were similar to the end outcomes observed in our cohort.
BDET is a relatively safe procedure. For this study, the procedure was performed under general anesthesia as it provides a controlled setting to perform balloon dilatation effectively by correct placement into the cartilaginous ET and adequate dilatation time which contribute to better outcome without complications. Evidence-based review of case series published by Miller and Elhassan reported an overall complications risk of 3% with no major adverse event in balloon dilatation. Preauricular emphysema and postoperative bleeding from the peritubal mucosal tear were the two most common postoperative complications reported following frequent sneezing after the procedure. Even though these complications are self-limiting, it is critical to control nasal symptoms. A potential major complication from the internal carotid artery rupture has not been reported. The safety marking and curvature of the balloon dilatation device have limited the dilatation to be confined to the cartilaginous portion of the ET. We did not observe these complications, however, a patient from the interventional group developed acute otitis media which resolved with symptomatic treatment. This could be explained by the possibility of early peritubal inflammation that impedes the secretion drainage from middle ear space with secondary bacterial infection.,
A limitation of this study was the inability to blind the patients and surgeons regarding the treatment options after randomization. This is likely to have an impact on the ETDQ-7 scoring. Nonetheless, in the same group of patients, we saw a significant improvement in objective measurements. Hence, we believe that the bias is minimal and the symptomatic improvement after balloon dilatation is reliable. We also had difficulty recruiting patients for the study during this critical period of the COVID-19 pandemic, and most patients refused endoscopic procedures, resulting in this small cohort of patients.
| Conclusion|| |
Symptomatic improvement of ETD following balloon dilatation can be observed within 6 weeks of treatment and is reliably documented using the ETDQ-7 and serial tympanograms. This safe and practical procedure is a striking option in the treatment of ETD and should be included in the treatment profile in centers with a high prevalence of middle ear disease. Continuous follow-up is imperative to evaluate symptoms and tympanic membrane appearance to justify long-term consistent effect of the procedure
This research was supported and approved by the Ethics Committee of Universiti Kebangsaan Malaysia Medical Centre and funded by UKM Fundamental Grant (FF-2019-291).
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2]