Tuboimpedance: A New Test of Eustachian Tube Function

Abstract

Objective Eustachian tube (ET) dysfunction is most frequently caused by a failure of the ET to adequately open; however, there is currently no reliable method of assessing this. Tubomanometry has recently shown good interindividual repeatability as a measure of ET function by measuring middle ear pressure after the application of regulated nasopharyngeal pressures during swallowing. We present the first reports of a novel test: middle ear impedance measurements during standard nasopharyngeal pressure application (tuboimpedance). We assess repeatability in healthy ears and any advantages over tubomanometry. Study Design Exploratory cohort diagnosis study. Setting Tertiary referral center. Subjects Twenty screened, healthy ears (10 volunteers). Methods Tubomanometry and tuboimpedance tests were performed while individuals swallowed with applied nasopharyngeal pressures of 20, 30, 40, and 50 mbar. Eustachian tube opening detection rate and test repeatability (measured by intraclass correlation coefficient [ICC]) for immediate and delayed repeats at each pressure were compared. Results ET opening was detected more frequently using tuboimpedance, with a 100% detection rate using a nasopharyngeal pressure of 30 mbar or more, compared to 88% to 96% with tubomanometry. Detection of ET opening at 20 mbar was possible with tuboimpedance. Repeatability of both tests was mostly strong (ICC >0.7) for both immediate and delayed repeats. Repeatability for the tubomanometry R value was only fair to moderate. Conclusion Tuboimpedance may provide a repeatable measure of ET opening that is easier to perform due to lower nasopharyngeal pressures required and fewer issues with poor ear-probe sealing. Further assessment in patients with different forms of ET dysfunction is required.

A Novel Eustachian Tube Test: Preliminary Research of Sonotubometry With Nasopharynx Under Pressure

“…Tuboimpedance is a novel test of ET function that more frequently detects ET openings compared with that of tubomanometry at more than or equal to 20 mbar in healthy subjects (20). Although tuboimpedance seems to be reliably superior to tubomanometry in detecting ET openings, this test can only be performed with intact tympanic membranes, while sonotubometry with nasopharynx under pressure (as well as tubomanometry) can be performed in both intact and perforated eardrums.…”

Advances in Eustachian tube function testing

“…As well as detecting those ears where the ET does not open, ET opening can be characterised as early or delayed, with delayed opening reported to indicate obstructive ETD 32 . The tuboimpedance test has also been described as a modification of tubomanometry, whereby ME pressure changes are detected with a tympanic impedance probe 33 …”

“…32 The tuboimpedance test has also been described as a modification of tubomanometry, whereby ME pressure changes are detected with a tympanic impedance probe. 33 In those patients with a tympanic membrane perforation or ventilation tube in situ, alternativeET opening tests are required, such as the inflation-deflation and forced response tests, the latter of which has been useful in a research setting to measure ET passive opening, 18 but has had less of a role in clinical practice.…”

Place of Tubomanometry in Patulous Eustachian Tube Diagnosis

“…9 However, all these techniques present limitations for PET diagnosis. [4][5][6][7] According to Esteve, 9 tubomanometry (TMM) establishes opening parameters of the eustachian tube, applying controlled pressure in the rhinopharynx and using tympanometry to measure pressure variations in the middle ear during swallowing. It is useful for evaluation of tubal obstruction.…”

“…To date, diagnostic procedures have combined different clinical and nonclinical evaluations. During the past decade, several studies have tried to devise objective tests to diagnose PET such as sonotubometry, 4,5 tuboimpedancemetry, 6 tubotympano‐aerodynamography, 7 nasal‐noise masking audiometry, 8 and tubotympanometry 9 . However, all these techniques present limitations for PET diagnosis 4–7 …”