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First Report on Shockwave Tubodilation Technique for Eustachian Tube Dysfunction

Archives of Otorhinolaryngology-Head & Neck Surgery. 2022;6(1):4
DOI: 10.24983/scitemed.aohns.2022.00157
Article Type: Original Article

Abstract

Objective: Eustachian tube dysfunction is known to play an influential role in causing middle ear diseases, which are often connected with nasal and sinusal disorders. Patients with severe symptoms may become resistant to medical treatment and surgical tubodilation. An innovative shockwave tubodilation technique was applied to patients with Eustachian tube dysfunction in this study. It has recently been demonstrated that shockwave tubodilation technique can be successfully applied to the tube level in urology. It has now been positioned at the coronary level, where it has been safely deployed. We believe this is the first study of its kind to demonstrate shockwaves in the Eustachian tube. This technique is based on the belief that shockwaves play an instrumental role in wound healing by regulating macrophages. The immunomodulation achieved by shockwaves may be underestimated as a benefit of clinical applications, which may be applicable to other macrophage-associated diseases. Accordingly, we hypothesized that shockwave tubodilation technique might be effective in treating Eustachian tube dysfunction through immunomodulation. This study aimed to evaluate the effectiveness of shockwave tubodilation in patients with Eustachian tube dysfunction.
Methods: Between November 2020 and February 2021, our study recruited 10 patients who displayed symptoms related to Eustachian tube dysfunction and then underwent shockwave tubodilation therapy. Patients received regular otolaryngological visits with audiological examinations. Our investigation consisted of the following procedures: an audiometric and impedance examination, rhinomanometry, otovideoendoscopy, the Italian nose obstruction symptom evaluation (I-NOSE) scale, the Sino-Nasal Outcome Test-22 (SNOT-22) questionnaire, and the Eustachian Tube Dysfunction Questionnaire-7 (ETDQ-7). Postoperative examinations and specialist examinations were performed for the patients after 2 weeks and 4 weeks following the procedure.
Results: The patients enrolled in the study ranged in age from 35 to 70 years old. Before surgery, 9 out of 10 patients (90%) had abnormal results on the audiometer, but only 5 out of 10 (50%) had abnormal results 2 weeks after surgery, and 2 out of 10 (20%) had abnormal results 4 weeks after surgery. Nine patients (90%) had abnormal impedance test results before surgery, but only 5 (50%) patients after surgery, and 2 (20%) patients 4 weeks after surgery. The rhinomanometer results were abnormal in 9 out of 10 cases (90%) prior to surgery, but only 4 of 10 patients (40%) had abnormal results 2 weeks following surgery, and only one patient (10%) had abnormal results 4 weeks after surgery. Based on the results of the responses to the SNOT-22, I-Nose, and ETDQ-7 questionnaires, patients who had undergone shockwave tubodilation therapy showed an improvement. There were no complications observed.
Conclusion: Based on subjective and objective assessments, shockwave tubodilation has been demonstrated to be effective in treating patients suffering from Eustachian tube dysfunction. The preliminary results have provided the impetus for us to continue our research and expand the number of cases studied to determine if the positive short-term outcomes of shockwave tubodilation have led to permanent improvement.

Keywords

  • Eustachian tube; minimally invasive; nasopharynx; otitis media; shockwave; tubodilation

Introduction

A Eustachian tube consists of an osseous posterolateral portion and a fibrocartilaginous anteromedial portion. An osseous portion is made up of the petrous part of the temporal bone, while a flexible portion is made up of the tubal cartilage and its surrounding tissue. The fibrocartilaginous portion plays the main role in the active function of the tube. Through suspensory ligaments, the fibrocartilaginous portion is connected to the skull base. In relation to the mediosagittal plane and to the horizontal plane, the longitudinal axis of the tube forms an angle. Adults have an angle of 45 degrees between the longitudinal axis of the cartilaginous part of the Eustachian tube and the mediosagittal plane, while infants have an angle of about 10 degrees. Adults usually have an average angle of 35 degrees between the Frankfurt horizontal plane (orbitomeatal plane) and the tubal longitudinal axis. Eustachian tubes range in length from 31 to 44 cm in adults but are only about half that length in newborns [1,2].

Several anatomic studies have been conducted concerning the Eustachian tube, however these were histopathologic studies performed on cadavers, making it difficult to correlate the findings with clinical circumstances [3-6]. Additionally, only a small number of subjects were included in these studies. With the use of the multiplanar reformation technique on computed tomography, it was found that patients with a stenotic Eustachian tube had a small bony framework, particularly near the isthmus, and a thick soft tissue lining, particularly near the tympanic cavity. The condition was considered to be one of the possible causes of tubal stenosis. These findings may prove helpful in identifying and managing Eustachian tube disorders [7].

Eustachian tube dysfunction is common among US adults; it is estimated that 4.6% of adults have Eustachian tube dysfunction, which rises to 48.5% when examined by questionnaire among patients with chronic rhinosinusitis [8]. Chronic sinonasal inflammation may lead to a dysfunctional Eustachian tube, which may then result in middle ear diseases [2,9]. Eustachian tube dysfunction is characterized by auricular fullness, hearing impairment, intermittent tinnitus, and a feeling of imbalance.

Eustachian tube balloon dilation, developed by Sudhoff [10,11], offers a minimally invasive treatment option for Eustachian tube dysfunction. During this procedure, an inflatable balloon catheter is inserted through the nasopharyngeal ostium into the Eustachian tube under an endoscopic view. The balloon catheter is then filled with saline to a pressure of ten bars and positioned for two minutes in the Eustachian tube. Following this step, the catheter is deflated and removed [12-14]. Our substantial experience in treating Eustachian tube dysfunction led us to develop a novel combined approach to Eustachian tube dysfunction using minimally invasive devices. It was found that the combined procedure is an effective, safe, and comprehensive treatment for tubal dysfunction in patients [9].

Research has shown that shock waves are key regulators of macrophage functions related to wound healing. This immunomodulatory effect may also apply to other diseases in which macrophages are involved, such as disorders of the Eustachian tube [15,16]. Based on this concept, we developed a novel shockwave tubodilation technique for patients with Eustachian tube dysfunction. We conducted a preliminary study to determine the feasibility and effectiveness of shockwave tubodilation technique in treating stenotic Eustachian tube dysfunction.

Methods

Between November 2020 and February 2021, we retrospectively enrolled 10 patients with refractory otitis media with effusion related to Eustachian tube dysfunction. It was reported that all the patients presented with rhinosinusitis as well as severe aural fullness and compensatory difficulties, which had failed to be resolved by medical treatment for five months. Decongestant and antihistamine nasal sprays were administered as part of the treatment for chronic rhinitis and associated Eustachian tube dysfunction. Patients under the age of fifteen, pregnant or lactating women, as well as those suffering from Meniere's syndrome, otosclerosis, dizziness, and tinnitus were excluded from the study. Patients with symptoms for less than three months were also excluded.

All patients had scheduled appointments with an otolaryngologist who performed an audiology examination. Among the examinations performed were audiometric and impedance testing, rhinomanometry, otovideoendoscopy, the Italian nose obstruction symptom evaluation (I-NOSE) scale, the Sino-Nasal Outcome Test-22 (SNOT-22) questionnaire, and the Eustachian Tube Dysfunction Questionnaire-7 (ETDQ-7). All of the patients showed symptoms associated with Eustachian tube dysfunction, as confirmed by the aforementioned examinations. Before minimally invasive treatment, CT scans were performed on patients' Eustachian tubes in order to assess cartilage length, bone structure, and the angle of the tube. Pure-tone audiometry was performed in accordance with international standards (ISO 8253-1). We obtained the pure tone average of four frequency thresholds at 500, 1000, 2000, and 4000 Hz.

A comprehensive treatment program was administered to ensure maximum effectiveness. The patients all underwent functional endoscopic sinus surgery, turbinoplasty involving removal of the middle and lower turbinates, tubal ostium shrinkage, and shockwave tubodilation technique. The procedure was performed under general anesthesia. This minimally invasive procedure involved the use of an optical fiber of 3 millimeters in diameter (Karl Storz, Tuttlingen, Germany) and shockwave tubodilation on the ipsilateral Eustachian tube. A shockwave intravascular lithotripsy system was used to perform the shockwave tubodilation technique [17]. In order to prevent damage to the mucosa of the Eustachian tube, the intravascular lithotripsy balloon was introduced within an Eicken smooth guide. After entering, the balloon was inflated to a pressure of 4 atmospheres. Two cycles of 10 shockwave pulses were delivered, and each cycle lasted 10 seconds. We allowed the balloon to remain inside the tube for an additional 40 seconds at 4 atm before removing it (Figure 1). The procedure was then repeated on the contralateral Eustachian tube. The interventions were performed at the Casa di Cura Santo Volto Hospital in Rome following approval by an institutional review board.

 

Figure 1. Endoscopic view of the shockwave tubodilation technique. (A) Preoperative view of the obstructive Eustachian tube. (B) Shockwave tubodilation. (C) The appearance of the Eustachian tube after 12 weeks of surgery.

Results

The patients that participated in the study ranged in age from 35 to 70 years old. A follow-up examination was performed at 2 weeks and 4 weeks postoperatively on the patients (Table 1). During the audiometer examination before surgery, 9 out of the 10 patients (90%) had abnormal results, but only 5 of the 10 patients (50%) had abnormal results 2 weeks after surgery, and 2 out of 10 patients (20%) had abnormal results 4 weeks following surgery. Among the 10 patients, 9 (90%) patients had abnormal results on their impedance tests prior to surgery, but only 5 (50%) patients had abnormal results 2 weeks after surgery, and 2 (20%) patients had abnormal results 4 weeks after surgery. There were abnormal rhinomanometer results in 9 out of 10 patients (90%) prior to surgery, but only 4 of 10 patients (40%) had abnormal rhinomanometer results 2 weeks following surgery, and only 1 (10%) patient had abnormal rhinomanometer results 4 weeks after surgery.

The mean score of the SNOT-22 questionare before surgery was 48, and the mean score was 4 and 0 respectively after surgery at 2 and 4 weeks postoperatively. In the I-NOSE questionnaire, the average value before surgery was 17, and the average score after surgery at 2 and 4 weeks postoperatively was 0 and 0. In the EDTQ-7 questionnaire, the mean score prior to surgery was 33, and 2 and 4 weeks after surgery the mean scores were 7 and 7, respectively.

In our study, there were no complications observed. This shockwave did not cause injury to the mucosa of the tubal ostium, nor did the shockwave damage the neighboring organs. A nosebleed was not experienced as a result of this shockwave.

 

Discussion

This novel shockwave tubodilation technique was specifically developed to treat Eustachian tube dysfunction in a safe, fast, minimally invasive manner. This approach was developed based on an established shockwave intravascular lithotripsy system. A recent study found that shockwaves play an important role in the regulation of macrophage functions in wound healing [16]. The immunomodulation represents an underappreciated effect of clinically applied shock waves, which could be exploited to treat other macrophage-associated conditions, such as Eustachian tube dysfunction [15,16]. The results of this study provide support for the use of shockwave tubodilation technique on patients suffering from disorders related to Eustachian tube dysfunction [16].

The shockwave tubodilation technique offers the advantage of a shorter procedure duration even in the most difficult cases (1 minute in total), allowing for a more effective procedure to be performed in a shorter time frame. In addition, the shockwave tubodilation technique permits a quicker execution of the surgical technique when compared to traditional balloon dilation (60 seconds as opposed to 120 seconds).

The present study is the first of its kind that demonstrates the use of shockwaves on the Eustachian tube. Furthermore, it summarizes the results of ten cases of refractory otitis media with effusion associated with Eustachian dysfunction. In addition, the insertion of a ventilation tube into the eardrum to treat Eustachian tube dysfunction often results in tympanic scarring and unhealing eardrum perforations, which require hospitalization and the associated expenses. A major benefit of the shockwave tubodilation technique is that it does not require hospitalization. In this way, the patient can return to normal life on the same day as the operation, resulting in an extremely low level of absenteeism from work.

This study emphasizes the importance of evaluating both subjective and objective data following shockwave tubodilation technique. In order to reach a conclusion regarding the effectiveness of this specific treatment modality, further investigation is required. In addition, a large-scale study will be required to determine the reliability and safety of this procedure. Furthermore, this technology has yet to be established whether it will have a long-term clinical impact. This study has another limitation in that the number of cases is relatively small. Currently, we are extending the number of cases so that the results of the study can be precisely validated. There is also the issue of the device's cost, which hopefully can be reduced in the future. It is also important to note that even though all patients had completely recovered from symptoms of tubal dysfunction approximately three months after surgery, they all underwent functional endoscopic sinus surgery, turbinoplasty, tubal ostium shrinkage, and shockwave tubodilation. Therefore, it may be challenging to determine the true therapeutic effects of each surgical procedure. It may be necessary to conduct further studies in order to clarify this issue.

Conclusion

The shockwave tubodilation technique has been demonstrated to be effective in treating patients suffering from otitis media with effusion resulting from Eustachian tube dysfunction. The preliminary results have motivated us to extend the number of cases studied and conduct further research to determine whether the positive short-term outcomes of shockwave tubodilation technique may have led to long-term improvements.

References

  1. Tysome JR, Sudhoff H. The role of the Eustachian tube in middle ear disease. Adv Otorhinolaryngol 2018;81:146-152. [View Article]
  2. Tos M. Importance of eustachian tube function in middle ear surgery. Ear Nose Throat J 1998;77(9):744-747. [View Article]
  3. Sade J, Luntz M, Yaniv E, Yurovitzki E, Berger G, Galrenter I. The eustachian tube lumen in chronic otitis media. Am J Otol 1986;7(6):439-442. [View Article]
  4. Sade J, Luntz M, Berger G. The eustachian tube profile in children. A quantitative histopathological study of the ET lumen and mucosal lining involvement in acute and secretory otitis media. Adv Otorhinolaryngol 1988;39:18-36. [View Article]
  5. Poe DS, Abou-Halawa A, Abdel-Razek O. Analysis of the dysfunctional eustachian tube by video endoscopy. Otol Neurotol 2001;22(5):590-595. [View Article]
  6. Takahashi H, Honjo I, Fujita A, Kurata K. Transtympanic endoscopic findings in patients with otitis media with effusion. Arch Otolaryngol Head Neck Surg 1990;116(10):1186-1189. [View Article]
  7. Yoshida H, Takahashi H, Morikawa M, Kobayashi T. Anatomy of the bony portion of the eustachian tube in tubal stenosis: Multiplanar reconstruction approach. Ann Otol Rhinol Laryngol 2007;116(9):681-686. [View Article]
  8. Shan A, Ward BK, Goman AM, et al. Prevalence of Eustachian tube dysfunction in adults in the United States. JAMA Otolaryngol Head Neck Surg 2019;145(10):974-975. [View Article]
  9. Di Rienzo Businco L, Di Mario A, Tombolini M, Mattei A, Lauriello M. Eustachian tuboplasty and shrinkage of ostial mucosa with new devices : Including a proposal of a classification system. HNO 2017;65(10):840-847. [View Article]
  10. Sudhoff H, Schroder S, Reineke U, Lehmann M, Korbmacher D, Ebmeyer J. [Therapy of chronic obstructive eustachian tube dysfunction: Evolution of applied therapies]. HNO 2013;61(6):477-482. [View Article]
  11. Todt I, Oppel F, Sudhoff H. Sensorineural hearing loss after balloon Eustachian tube dilatation. Front Surg 2021;8:615360. [View Article]
  12. Ockermann T, Reineke U, Upile T, Ebmeyer J, Sudhoff HH. Balloon dilatation eustachian tuboplasty: A clinical study. Laryngoscope 2010;120(7):1411-1416. [View Article]
  13. Poe DS, Silvola J, Pyykko I. Balloon dilation of the cartilaginous eustachian tube. Otolaryngol Head Neck Surg 2011;144(4):563-569. [View Article]
  14. Liu W, Chen M, Hao J, et al. [The short-term and long-term efficacy of balloon dilatation Eustachian tuboplasty and tympanostomy tubes in children patients with recurrent otitis media with effusion]. Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2020;34(3):210-214. [View Article]
  15. Jecker P, Pabst R, Westermann J. Proliferating macrophages, dendritic cells, natural killer cells, T and B lymphocytes in the middle ear and Eustachian tube mucosa during experimental acute otitis media in the rat. Clin Exp Immunol 2001;126(3):421-425. [View Article]
  16. Holsapple JS, Cooper B, Berry SH, et al. Low intensity shockwave treatment modulates macrophage functions beneficial to healing chronic wounds. Int J Mol Sci 2021;22(15). [View Article]
  17. Brinton TJ, Ali ZA, Hill JM, et al. Feasibility of shockwave coronary intravascular lithotripsy for the treatment of calcified coronary stenoses. Circulation 2019;139(6):834-836. [View Article]

Editorial Information

Publication History

Received date: November 09, 2021
Accepted date: January 05, 2022
Published date: February 28, 2022

Ethics Approval and Consent to Participate

The study is in accordance with the ethical standards of the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Funding

This research has received no specific grant from any funding agency either in the public, commercial, or not-for-profit sectors.

Conflict of Interest

There are no conflicts of interest declared by either the authors or the contributors of this article, which is their intellectual property.

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Copyright

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  1. Minimally Invasive Otorhinolaryngological Surgery Unit, Institute of Medicine and Science, CONI Sport e Salute, Rome, Italy
  2. Otorhinolaryngology Unit, Casa di Cura Santo Volto, Rome, Italy
  1. Minimally Invasive Otorhinolaryngological Surgery Unit, Institute of Medicine and Science, CONI Sport e Salute, Rome, Italy
  2. Otorhinolaryngology Unit, Casa di Cura Santo Volto, Rome, Italy
  1. Minimally Invasive Otorhinolaryngological Surgery Unit, Institute of Medicine and Science, CONI Sport e Salute, Rome, Italy
  2. Otorhinolaryngology Unit, Casa di Cura Santo Volto, Rome, Italy
  1. Minimally Invasive Otorhinolaryngological Surgery Unit, Institute of Medicine and Science, CONI Sport e Salute, Rome, Italy
  2. Otorhinolaryngology Unit, Casa di Cura Santo Volto, Rome, Italy

Address: Via Agrigento 6, 00161 Roma, Italy
Figure 1.png
Figure 1. Endoscopic view of the shockwave tubodilation technique. (A) Preoperative view of the obstructive Eustachian tube. (B) Shockwave tubodilation. (C) The appearance of the Eustachian tube after 12 weeks of surgery.
Table 1.jpg
Table 1. Subjective and Objective Assessments Before and After Shockwave Tubodilation Technique

Reviewer 1 Comments

  1. The studies regarding balloon dilation of the Eustachian tube have been reported previously, and the outcomes showed the effectiveness and safety of the technique. Authors should provide a brief review of the literature addressing the limitations and/or flaws in previous studies and the reasons why they believe Shockwave can improve the outcomes of balloon dilation of the Eustachian tube.
    ResponseResearch has shown that shock waves are key regulators of macrophage functions related to wound healing. This immunomodulatory effect may also apply to other diseases in which macrophages are involved, such as disorders of the Eustachian tube. Based on this concept, we developed a novel shockwave tubodilation technique for patients with Eustachian tube dysfunction. We conducted a preliminary study to determine the feasibility and effectiveness of shockwave tubodilation technique in treating stenotic Eustachian tube dysfunction.
     
  2. The authors stated that the balloons for tubal dilation have proved to be of very low costs. However, cost-effectiveness of such advanced technology with the application of shockwave should be further clarified.
    ResponseCompared to traditional therapy, we defined this treatment as low cost. For example, the insertion of a ventilation tube into the eardrum often results in tympanic scarring and unhealing eardrum perforations, which require hospitalization and the associated expenses. A major benefit of the shockwave tubodilation technique is that it does not require hospitalization. In this way, the patient can return to normal life on the same day as the operation, resulting in an extremely low level of absenteeism from work. The issue has been revised in accordance with your suggestions.
     
  3. Is the study performed prospectively or retrospectively?
    ResponseThe study was retrospective in nature.

Reviewer 2 Comments

  1. Intravascular shockwave lithotripsy offers a novel treatment option for severely calcified plaques in coronary and peripheral vessels. It is useful to modify calcium circumferentially and transmurally. Although patients with Eustachian tube dysfunction have tubal compliance abnormality, I am curious about the purpose of applying shockwave for patients with Eustachian tube dysfunction. Is shockwave useful for the treatment of Eustachian tube dysfunction? The authors need to explain the rationale for applying Shockwave in these patients.
    ResponseEustachian tube balloon dilation, developed by Sudhoff, offers a minimally invasive treatment option for Eustachian tube dysfunction. During this procedure, an inflatable balloon catheter is inserted through the nasopharyngeal ostium into the Eustachian tube under an endoscopic view. The balloon catheter is then filled with saline to a pressure of ten bars and positioned for two minutes in the Eustachian tube. Following this step, the catheter is deflated and removed. Our substantial experience in treating Eustachian tube dysfunction led us to develop a novel combined approach to Eustachian tube dysfunction using minimally invasive devices. It was found that the combined procedure is an effective, safe, and comprehensive treatment for tubal dysfunction in patients. Research has shown that shock waves are key regulators of macrophage functions related to wound healing. This immunomodulatory effect may also apply to other diseases in which macrophages are involved, such as disorders of the Eustachian tube. Based on this concept, we developed a novel shockwave tubodilation technique for patients with Eustachian tube dysfunction. We conducted a preliminary study to determine the feasibility and effectiveness of shockwave tubodilation technique in treating stenotic Eustachian tube dysfunction.
     
  2. The authors reported that in their study they have seen a “significant” improvement of “this” in both subjective and objective data and a very low rate of functional recovery. Do the authors mean a significant improvement of the Shockwave technique? How do the authors define “significant”?
    ResponseWe did not calculate the P value when comparing the preoperative and postoperative outcomes due to the small number of cases. We have therefore deleted the term "significant".
     
  3. Although the results of the study are preliminary, the authors are suggested to offer the descriptive statistics in detail using tables, charts, or graphs to summarize data in a constructive manner. For instance, in Table 1, I do not understand the differences between the variables between preoperatively and postoperatively. Do the authors mean abnormal examination results of the impedance test, rhinomanometry, and questionnaires?
    ResponseThe table shown in this article represents the altered examinations of the various tests that were performed, as well as the assessment of these examinations over time to determine how many of the altered examinations remained after the shockwave therapy.

Reviewer 3 Comments

  1. Despite in all these patients there was a very rapid and efficient response and recovery from the ear muffling disorder and complete recovery from symptoms related to tubal dysfunction occurs approximately 3 months later, all these patients presenting with rhinosinusitis and tubal stenosis underwent minimally invasive FESS, turbinoplasty of the middle and lower turbinates, TOS and tubodilation by intravascular lithotripsy. It may be difficult to determine the true therapeutic effects of each surgical procedure on the patients.
    ResponseIt is also important to note that even though all patients had completely recovered from symptoms of tubal dysfunction approximately three months after surgery, they all underwent functional endoscopic sinus surgery, turbinoplasty, tubal ostium shrinkage, and shockwave tubodilation. Therefore, it may be challenging to determine the true therapeutic effects of each surgical procedure. It may be necessary to conduct further studies in order to clarify this issue. These points have been added in the Discussion section.
     
  2. In table 1, the variable “drugs” needs to be further clarified. Also, what does an audiometric examination mean? Does that refer to pure tone audiometry?
    ResponseThe term "drugs" has been changed to "medical therapy" (patients who used medical therapy before surgery). Pure-tone audiometry was performed in accordance with international standards (ISO 8253-1). We obtained the pure tone average of four frequency thresholds at 500, 1000, 2000, and 4000 Hz.
     
  3. Authors should include a comprehensive description of the strengths and limitations of the research.
    ResponseThis study emphasizes the importance of evaluating both subjective and objective data following shockwave tubodilation technique. In order to reach a conclusion regarding the effectiveness of this specific treatment modality, further investigation is required. A large-scale study will be required to determine the reliability and safety of this procedure. This technology has yet to be established whether it will have a long-term clinical impact. This study has another limitation in that the number of cases is relatively small. Currently, we are extending the number of cases so that the results of the study can be precisely validated. There is also the issue of the device's cost, which hopefully can be reduced in the future.

Reviewer 4 Comments

  1. The interventions were performed at the Casa di Cura Santo Volto hospital with the approval of the Statement of institutional review board. I wonder if the authors refer to IRB of Casa di Cura Santo Volto hospital or other institutions? This needs to be clarified.
    ResponseThe interventions were performed at the Casa di Cura Santo Volto Hospital in Rome following approval by its institutional review board.
     
  2. The authors should provide with the pre-operative and post-operative photos to facilitate understanding of the technique and the associated clinical outcomes.
    ResponseWe have provided preoperative, intraoperative, and postoperative photos.
     
  3. Authors must specify the criteria used for the inclusion and exclusion of participants in study group.
    ResponseBetween November 2020 and February 2021, we retrospectively enrolled 10 patients with refractory otitis media with effusion related to Eustachian tube dysfunction. It was reported that all the patients presented with rhinosinusitis as well as severe aural fullness and compensatory difficulties, which had failed to be resolved by medical treatment for five months. Decongestant and antihistamine nasal sprays were administered as part of the treatment for chronic rhinitis and associated Eustachian tube dysfunction. Patients under the age of fifteen, pregnant or lactating women, as well as those suffering from Meniere's syndrome, otosclerosis, dizziness, and tinnitus were excluded from the study. Patients with symptoms for less than three months were also excluded.

Editorial Comments

  1. The authors need to define abbreviations at their first mention in the text (e.g., SNOT 22, ETDQ-7, and TOS), including those in the table.
    ResponseThese abbreviations have been defined accordingly.
     
  2. The variable "drugs" in table 1 should be further clarified.
    ResponseThe term "drugs" has been changed to "medical therapy" (patients who used medical therapy before surgery).