Outcome Measures for Baro-Challenge-Induced Eustachian Tube Dysfunction: A Systematic Review

Abstract

Objectives: Baro-challenge-induced Eustachian tube dysfunction (baro-induced ETD) is characterized by failure of the Eustachian tube (ET) to open adequately to permit middle-ear pressure regulation during ambient pressure changes. There are no well-characterized tests for identifying the condition, which makes both patient diagnosis and research into treatment efficacy challenging. This systematic review evaluates ET function tests as potential outcome measures for baro-induced ETD.

Data sources: MEDLINE and CENTRAL were searched (database inception to March 2017) and reference lists reviewed for all relevant English Language articles.

Study selection: Tests in included studies were required to measure ET function in patients reporting baro-induced ear symptoms or barotrauma.

Data extraction: Data were extracted in a standardized manner, and studies assessed according to Standards for Reporting of Diagnostic Accuracy Studies (STARD) criteria. The primary outcome of interest was the accuracy of ET function tests.

Data synthesis: Heterogeneity of subject demographics, ET function test methodology, and reference standards only permitted narrative systematic review.

Conclusion: Sixteen studies involving seven different types of ET function tests were identified. The nine-step test was the most commonly used outcome measure, with overall test sensitivity and specificity ranges of 37 to 100% and 57 to 100%, respectively. Tympanometry test sensitivity was consistently poor (0-50%) while specificity was higher (52-97%). Published accuracy data for other ET function tests and test combinations were limited. Currently, no single test can be recommended for use in clinical practice. A combination of the nine-step test with other objective tests or patient-reported measures appears most promising as a core set of outcome measures for baro-induced ETD.