The repeatability of tests of eustachian tube function in healthy ears.

OBJECTIVES/HYPOTHESIS: Many objective tests of eustachian tube (ET) function have been devised for clinical and research use but they have not been directly compared or characterized. As a first step to identifying tests to incorporate into an outcome set for ET dysfunction, we assessed repeatability of a panel of eight of these tests in healthy ears. STUDY DESIGN: Comparison of eight tests of ET function. METHODS: The following tests were investigated in combination with Valsalva, Toynbee, swallow, or sniff maneuvers: 1) patient-reported ET opening, 2) observed tympanic membrane movement, 3) continuous impedance, 4) canal manometry, 5) sonotubometry, 6) nine-step test, 7) tubomanometry, and 8) tympanometry at rest. Forty-two healthy volunteers were recruited. Each test was performed in 20 different ears and repeated immediately three times in each cycle, with four cycles performed at 20-minute intervals. Repeatability of detected ET opening was compared using the intraclass correlation coefficient (ICC). RESULTS: Mean ET opening rate with each test ranged from 30% to 95%. Variation in detection of ET opening was less when tests were repeated immediately (ICC = 0.61) when compared to between cycles (ICC = 0.49), suggesting there may be significant changes in ET function in the short term. Tubomanometry was the only test to combine a detected ET opening rate of >85% and substantial agreement of results (ICC >0.61) between test cycles. CONCLUSIONS: Tubomanometry was the most reliable test at detecting ET opening. When tests of ET function are used in clinical practice, they should be performed more than once to gain a more reliable result. LEVEL OF EVIDENCE: 3b. Laryngoscope, 127:2619-2626, 2017.