Can Eustachian tube dysfunction come and go and show on a tympanogram?

Can Eustachian Tube Dysfunction Show on Tympanometry and Fluctuate Over Time?

Yes, Eustachian tube dysfunction (ETD) can absolutely come and go, and tympanometry is one of the primary objective tools used to detect it, though findings may vary depending on when testing occurs relative to symptom fluctuation.

Tympanometry Findings in ETD

Tympanometry provides objective assessment of middle ear function and can detect ETD-related changes, though the specific pattern depends on the type and severity of dysfunction:

• Type B (flat) tympanogram indicates middle ear effusion or severely impaired tympanic membrane mobility, commonly seen with obstructive ETD when fluid accumulates 1
• Type C tympanogram shows negative middle ear pressure, reflecting incomplete or intermittent ETD where the Eustachian tube fails to adequately ventilate the middle ear 1
• Normal Type A tympanogram can occur when ETD temporarily resolves or between episodes of dysfunction 1

The American Academy of Otolaryngology-Head and Neck Surgery guidelines note that tympanometry has "significant utility as a prognostic indicator" for persistent middle ear problems, even when the duration of effusion is unknown 1. However, pneumatic otoscopy remains the preferred primary diagnostic tool, with tympanometry serving as a valuable adjunctive test 1.

Fluctuating Nature of ETD

ETD commonly fluctuates in severity and can completely resolve and recur:

• Middle ear effusion following acute otitis media demonstrates this variability, with 70% persistence at 2 weeks, 40% at 1 month, 20% at 2 months, and only 10% at 3 months 1
• Chronic OME (≥3 months duration) shows much slower resolution rates: only 19% spontaneous resolution after an additional 3 months, 25% at 6 months, and 31% at 12 months 1
• Patulous ETD (abnormally patent tube) is particularly known for fluctuating symptoms, with 65% of patients reporting symptoms that increase in frequency and duration over time, often exacerbated by exercise and improved with head-dependent positioning 2

Clinical Implications for Diagnosis

The intermittent nature of ETD creates diagnostic challenges:

• A child referred for suspected ETD with effusion may have complete resolution of middle ear fluid by the time of specialist evaluation, even if recently documented by another clinician 1
• The absence of MEE at assessment suggests favorable Eustachian tube function and good prognosis, even in patients with recurrent acute otitis media 1
• Serial tympanometry over time is more informative than a single measurement, as it can capture the fluctuating nature of dysfunction 1

Monitoring Recommendations

For patients with suspected or confirmed ETD:

• Reevaluation at 3- to 6-month intervals is recommended for children with chronic OME who don't receive tympanostomy tubes, continuing until effusion resolves, significant hearing loss is detected, or structural abnormalities develop 1
• Repeat hearing testing in 3-6 months should be performed if OME persists and watchful waiting continues 1
• Tympanometry can document resolution by showing conversion from Type B to normal Type A, though this occurs in only 20% of preschool children after 3 months and 28% after 6 months with chronic effusion 1

Common Pitfalls

• Single normal tympanogram doesn't exclude ETD: Testing during a period of temporary resolution may miss intermittent dysfunction 1
• Type B tympanogram has poor short-term prognosis: Even with unknown effusion duration, this finding predicts persistent problems requiring closer monitoring 1
• Relying solely on tympanometry for diagnosis: Pneumatic otoscopy should be the primary diagnostic method, with tympanometry used for confirmation and monitoring 1

The fluctuating nature of ETD means that negative findings on a single tympanogram don't rule out the diagnosis, particularly if symptoms are intermittent or if testing occurs during a period of temporary improvement 1, 2.