Continuing Education Activity

Eustachian tube dysfunction (ETD) is the failure of the Eustachian tube to maintain pressure equalization or mucociliary transport. This is categorized as acute (less than 3 months presentation) or chronic ETD (more than 3 months). ETD affects 1% of the population, with symptoms including aural fullness or ‘popping sounds,’ reduced hearing, tinnitus, autophony, otalgia, and imbalance. It can be broadly categorized into baro-challenged induced, patulous, and dilatory ETD. This activity outlines the types of Eustachian tube dysfunction, the associated risk factors, and the appropriate evaluation and management of the condition by an interprofessional team.

Objectives:

• Identify the typical patient history associated with dysfunction of the Eustachian tubes.
• Assess the pathophysiology of Eustachian tube dysfunction.
• Evaluate the treatment considerations for patients with Eustachian tube dysfunction.
• Communicate the importance of collaboration among the interprofessional team to improve outcomes for pediatric patients affected by Eustachian tube dysfunction, who are at risk of speech and language delay.

Introduction

The Eustachian tube, also termed the pharyngotympanic or auditory tube, is vital in regulating middle ear homeostasis, with complex anatomy designed to achieve this function. It travels medially from the middle ear, directing down and forwards to open just posterior to the end of the inferior turbinate—the bony lateral third travels past both squamous and petrous portions of the temporal bone. The medial two-thirds is fibrocartilaginous, opening out into the nasopharynx as a mucosal elevation known as the torus tubarius. The tube opens on positive pressure, eg, yawning, sneezing, swallowing, and the Valsalva maneuver, by contraction of the levator veli palatini and tensor veli palatini muscles. Through the Eustachian tube's complex structure, it can carry out its 3 main functions:

Firstly, by having a patent and open Eustachian tube, the pressure of the middle ear is equalized to that of the nasopharynx (ie, towards atmospheric pressure). This has assistance from active mucosal gas exchange within the middle ear. With the maintenance of middle ear pressure, tympanic membrane compliance is optimized for hearing. Secondly, it contains tube mucociliary transport. This consists of ciliated cells that clear inflammatory products and secretions from the middle ear and Eustachian tube, transporting them toward the direction of the nasopharynx for elimination. Lastly, a functioning Eustachian tube protects the middle ear from loud sounds and potential hazards, including pathogens and secretions from the nasopharynx.

Eustachian tube dysfunction (ETD) is the failure of the Eustachian tube to maintain any of the 3 roles mentioned above. This is categorized as acute (less than 3 months presentation) or chronic ETD (more than 3 months). ETD affects 1% of the population, with symptoms including aural fullness or 'popping sounds,' reduced hearing, tinnitus, autophony, otalgia, and imbalance. It can be broadly categorized into baro-challenged induced, patulous, and dilatory ETD.[1][2][3]

Etiology

Baro-challenge-induced ETD describes the failure of the Eustachian tube to open with the surrounding pressure changes, thereby inhibiting the regulation of middle-ear pressure. Patients have normal otoscopy and tympanometry findings, as the failure of tube opening is situation-specific and arises with increased atmospheric pressure, eg, deep-sea diving or descent from altitude. The stress imposed on the mucosal surfaces of the Eustachian tube by repetitive equalization maneuvers from the increased atmospheric pressure leads to localized inflammation and mucosal edema. This affects the ability to make subsequent attempts at opening and clearance. By applying oral or topical decongestants to treat baro-challenge-induced ETD, it is thought that mucosal edema and local tissue hyperemia are reduced, thereby shrinking the nasopharyngeal mucosa and improving Eustachian tube patency.

Patulous ETD is caused by an overtly patent Eustachian tube, whereby the failed tube closure at rest provides continuous communication between the nasopharynx and the middle ear. This creates the reported symptom of autophony, with habitual sniffing to help alleviate self-vocalization. Physiological causes of dilatory ETD involve the development of inflammation and mucosal edema caused by episodes of rhinitis, upper respiratory tract infection, or gastro-oesophageal reflux disease, which leads to blockage of the orifice and dysfunction. Malignancy such as nasopharyngeal carcinoma can present with unilateral obstruction and must be excluded, with benign causes of obstruction including adenoidal hypertrophy and sequelae following adenoidectomy. Aural fullness is a common symptom due to negative middle ear pressure build-up.[4][5][6]

Epidemiology

Prevalence is greater in children than adults, with recent studies demonstrating 0.77 adult visits to every 1 pediatric clinic visit for ETD. An estimated 90% of children develop otitis media with effusion, a recognized sequela of ETD, before starting school. Approximately 1% of the adult population is diagnosed with ETD. Males are more likely to be diagnosed before the age of 20, with females more likely affected at older ages. No statistically significant difference between seasons has been proven.[7]

History and Physical

History includes determining any precipitating factors that may lead to inflammation or edema of the mucosal surfaces, leading to reduced patency of the Eustachian tube, including gastro-oesophageal reflux disease, rhinosinusitis, Samter’s triad, allergies, and recent upper respiratory tract infections. A history of adenoidectomy is a risk factor, and it is important to establish a family history of ETD or diseases of reduced mucociliary clearance, eg, Kartagener syndrome and cystic fibrosis. Down syndrome and cleft palate disorders have an association with ETD. Irritants that lead to inflammation include exposure to cigarette smoking and environmental allergens. Has the patient participated in diving or hiking at high altitudes? Ensure that intranasal medication, including oxymetazoline and corticosteroids, is explored.

The examination involves a head and neck examination, with otoscopy required to visualize for tympanic membrane retractions and evidence of negative middle ear pressures. Occasionally, hemotympanum is present in baro-challenge-induced ETD. Visualize the oropharynx and perform anterior rhinoscopy. Flexible nasoendoscopy should be included to examine the nasal mucosa for signs of inflammation or edema and the larynx for evidence of gastro-oesophageal reflux disease. Flexible nasoendoscopy provides access to the postnasal space, including a view of the contralateral nasopharyngeal orifice of the Eustachian tube. The valve mucosa is S-shaped when closed at resting state and rounded when dilated. Dilation should occur with swallowing.

Evaluation

Tympanic insufflation is performed to demonstrate active negative pressure, and a type C Tympanogram suggests negative resting middle ear pressures. Audiological tests must be completed using pure tone audiometry and Rinne and Weber tuning fork tests. The Eustachian Tube Dysfunction Patient Questionnaire (ETDQ-7) aims to screen for patient-reported severity of ETD using a scoring system. It consists of 7 separate questions, scored between 1 (no problem) and 7 (severe problem). A mean overall score of more than 2.0 indicates the presence of ETD.[8]

Treatment / Management

Treatment of ETD is dependent on the likely cause of dysfunction:

• Gastroesophageal reflux disease is addressed with lifestyle changes, including losing weight and dietary modifications to reduce acid production. Anti-acid medication, such as proton pump inhibitors, may be considered.
• If possible, try lifestyle changes to avoid potential allergens. Medical interventions include antihistamines and nasal corticosteroid medication.
• If indicated, treatment of rhinosinusitis should commence. Immunosuppressive agents are required for granulomatous diseases, eg, sarcoidosis and granulomatosis with polyangiitis (Wegener disease).
• Surgical dilatation of the Eustachian tube is performed using a Eustachian tube balloon catheter, with studies demonstrating improvement of the ETDQ-7 score at 12 months follow-up. ETD from otitis media with effusion is commonly managed with tympanostomy tube insertion
• Patients should be considered for adenoidectomy if adenoid hypertrophy is thought to be the main contributing factor to ETD. This is more common in children, who may present with middle ear effusion. Using auto-inflation devices to reopen the Eustachian tube by raising the pressure in the nose has shown favorable results for correcting middle ear pressure and fluid clearance.[9][10]

Differential Diagnosis

Autophony is not limited to patulous ETD. Symptoms may include superior canal dehiscence and a foreign body within the external ear canal. Temporomandibular joint dysfunction may present with ‘popping’ noises and associated reduced hearing; however, it is also associated with discomfort upon jaw movement.

Prognosis

The outcome is dependent on the underlying cause and compliance with treatment. However, pediatric ETD generally improves and resolves with the maturation of the Eustachian tube and its surrounding muscles, aiding air ventilation- this usually occurs at 7 years of age.[11]

Complications

Complications of untreated ETD include conductive hearing loss, chronic otitis media, otitis media with effusion (glue ear) and its sequelae, and eardrum retraction.[12]

Deterrence and Patient Education

Deterrence and patient education should center around information regarding healthy lifestyle changes, such as smoking cessation and dietary changes, that can reduce the recurrence of inflammation and disease and identify cases that require medical review and intervention.

Enhancing Healthcare Team Outcomes

Although present at any stage in life, ETD is more prevalent in children due to the need for further growth of the eustachian tube. Compared to adults, pediatric eustachian tubes have a shallow angle to the horizontal plane, increasing the risk of poor middle ear secretion and resulting otitis media with effusion. Sequalae of ETD include episodes of acute otitis media or otitis media with effusion, with subsequent progression towards speech and hearing problems, disturbances in attention, limited vocabulary, and sleep deprivation. This reduces the child’s overall quality of life and causes stress and concern for the parent/caregiver. Schoolteachers or parents often highlight initial concerns regarding the child's hearing or disruptive behavior within the class setting, prompting the family physician to perform a thorough otology examination and subsequent referral for further investigations. Audiologists perform a pivotal role in determining the severity, type, and laterality of hearing loss in the patient. This enables clinicians to appropriately counsel families regarding reduced hearing and the potential impact. Speech and language pathologists may discuss strategies for minimizing the impact within the home and learning environment (eg, preferential seating in the front of the classroom, facing the child and speaking, using visual cues, etc). With this holistic care between different health professionals, the physician can focus on patient-based care and appropriately decide between conservative, medical, or surgical (eg, adenoidectomy and tympanostomy tube insertion) management based on the patient’s needs.[13]

Review Questions

• Access free multiple choice questions on this topic.
• Click here for a simplified version.
• Comment on this article.

References

1.

Martino E, Di Thaden R, Krombach GA, Westhofen M. [Function tests for the Eustachian tube. Current knowledge]. HNO. 2004 Nov;52(11):1029-39; quiz 1040. [PubMed: 15338038]

2.

Ozturk K, Snyderman CH, Sando I. Do mucosal folds in the eustachian tube function as microturbinates? Laryngoscope. 2011 Apr;121(4):801-4. [PubMed: 21344453]

3.

Jesić S, Nesić V. [Mucociliary transport in Eustachian tubes in chronic suppurative otitis media]. Srp Arh Celok Lek. 2004 May-Jun;132(5-6):148-51. [PubMed: 15493584]

4.

Schilder AG, Bhutta MF, Butler CC, Holy C, Levine LH, Kvaerner KJ, Norman G, Pennings RJ, Poe D, Silvola JT, Sudhoff H, Lund VJ. Eustachian tube dysfunction: consensus statement on definition, types, clinical presentation and diagnosis. Clin Otolaryngol. 2015 Oct;40(5):407-11. [PMC free article: PMC4600223] [PubMed: 26347263]

5.

Tailor BV, Smith ME, Hutchinson PJA, Tysome JR. Outcome Measures for Baro-Challenge-Induced Eustachian Tube Dysfunction: A Systematic Review. Otol Neurotol. 2018 Feb;39(2):138-149. [PubMed: 29315176]

6.

Bance M, Tysome JR, Smith ME. Patulous Eustachian tube (PET), a practical overview. World J Otorhinolaryngol Head Neck Surg. 2019 Sep;5(3):137-142. [PMC free article: PMC6849362] [PubMed: 31750425]

7.

Vila PM, Thomas T, Liu C, Poe D, Shin JJ. The Burden and Epidemiology of Eustachian Tube Dysfunction in Adults. Otolaryngol Head Neck Surg. 2017 Feb;156(2):278-284. [PubMed: 28116997]

8.

McCoul ED, Anand VK, Christos PJ. Validating the clinical assessment of eustachian tube dysfunction: The Eustachian Tube Dysfunction Questionnaire (ETDQ-7). Laryngoscope. 2012 May;122(5):1137-41. [PMC free article: PMC3612400] [PubMed: 22374681]

9.

Anand V, Poe D, Dean M, Roberts W, Stolovitzky P, Hoffmann K, Nachlas N, Light J, Widick M, Sugrue J, Elliott CL, Rosenberg S, Guillory P, Brown N, Syms C, Hilton C, McElveen J, Singh A, Weiss R, Arriaga M, Leopold J. Balloon Dilation of the Eustachian Tube: 12-Month Follow-up of the Randomized Controlled Trial Treatment Group. Otolaryngol Head Neck Surg. 2019 Apr;160(4):687-694. [PubMed: 30620688]

10.

Perera R, Glasziou PP, Heneghan CJ, McLellan J, Williamson I. Autoinflation for hearing loss associated with otitis media with effusion. Cochrane Database Syst Rev. 2013 May 31;2013(5):CD006285. [PMC free article: PMC11357689] [PubMed: 23728660]

11.

Singh GB, Sidhu TS, Sharma A, Singh N. Tympanoplasty type I in children--an evaluative study. Int J Pediatr Otorhinolaryngol. 2005 Aug;69(8):1071-6. [PubMed: 16005349]

12.

Fireman P. Otitis media and eustachian tube dysfunction: connection to allergic rhinitis. J Allergy Clin Immunol. 1997 Feb;99(2):S787-97. [PubMed: 9042072]

13.

Rosenfeld RM, Shin JJ, Schwartz SR, Coggins R, Gagnon L, Hackell JM, Hoelting D, Hunter LL, Kummer AW, Payne SC, Poe DS, Veling M, Vila PM, Walsh SA, Corrigan MD. Clinical Practice Guideline: Otitis Media with Effusion (Update). Otolaryngol Head Neck Surg. 2016 Feb;154(1 Suppl):S1-S41. [PubMed: 26832942]

Disclosure: Sahar Hamrang-Yousefi declares no relevant financial relationships with ineligible companies.

Disclosure: Jimmy Ng declares no relevant financial relationships with ineligible companies.

Disclosure: Claudio Andaloro declares no relevant financial relationships with ineligible companies.