The tube that connects the middle ear to the nasopharynx - the eustachian tube-provides ventilation and drainage for the middle ear cleft. It is normally dosed, opening only during swallowing or yawning. When eustachian tube function is compromised, air trapped within the middle ear becomes absorbed and negative pressure results. The most common causes of eustachian tube dysfunction are diseases associated with edema of the tubal lining, such as viral upper respiratory tract infections and allergy. The patient usually reports a sense of fullness in the ear and mild to moderate impairment of hearing. When the tube is only partially blocked, swallowing or yawning may elicit a popping or crackling sound.
Examination may reveal retraction of the tympanic membrane and decreased mobility on pneumatic otoscopy. Following a viral illness, this disorder is usually transient, lasting days to weeks. Treatment with systemic and intranasal decongestants (eg, pseudoephedrine, 60 mg orally every 4 hours; oxymetazoline, 0.05% spray every 8 - 1 2 hours) combined with autoinflation by forced exhalation against closed nostrils may hasten relief. Autoinflation should not be recommended to patients with active intranasal infection, since this maneuver may precipitate middle ear infection. Allergic patients may also benefit from desensitization or intranasal corticosteroids ( eg, beclomethasone dipropionate, two sprays in each nostril twice daily for 2-6 weeks). Air travel, rapid altitudinal change, and underwater diving should be avoided during an active phase of the disease.
Conversely, an overly patent eustachian tube, termed "patulous eustachian tube;' is a relatively uncommon problem though may be quite distressing. Typical complaints include fullness in the ear and autophony, an exaggerated ability to hear oneself breathe and speak. A patulous eustachian tube may develop during rapid weight loss, or it may be idiopathic. In contrast to a hypofunctioning eustachian tube, the aural pressure is often made worse by exertion and may diminish during an upper respiratory tract infection. Although physical examination is usually normal, respiratory excursions of the tympanic membrane may occasionally be detected during vigorous breathing. Treatment includes avoidance of decongestant products, insertion of a ventilating tube to reduce the outward stretch of the eardrum during phonation and, rarely, surgical procedure in the eustachian tube.
Source:(2017 CURRENT Medical Diagnosis & Treatment)
- Norman G et al. Systematic review of the limited evidence base for treatments of Eustachian tube dysfunction: a health technology assessment. Clin Otolaryngol. 2014 Feb;39 (1) :6-2 1 . [PMID: 24438176]
- Randrup TS et al. Balloon eustachian tuboplasty: a systematic review. Otolaryngol Head Neck Surg. 2015 Mar; l 52(3):383-92. [PMID: 25605694]