Prospective Validation of Tubomanometry in Children With Normal Eustachian Tube Function.

OBJECTIVES: Tubomanometry (TMM), described initially by Estève, is a relatively new manometric method for testing the eustachian tube function (ETF). This study presents the analysis of the measurement of ETF of healthy children by TMM, which has, to date, not been properly evaluated. The objectives of the study were to establish normative data for TMM and to demonstrate TMM as a reliable and valid method for measuring ETF in children. DESIGN: The evaluation, after initial power analysis, comprised 35 children from 6 to 15 years of age with an intact tympanic membrane, no severe ET dysfunction, and less than three inflammations of the middle ear in their medical history. TMM was performed twice at three pressure levels for both ears. Statistical assessment of the various parameters of TMM was performed with emphasis on the R value and possible age dependency. RESULTS: The 90th percentile for the R value was calculated to be 1.12. No clinically relevant age effect regarding the use of TMM as a screening method for children was found. Healthy children showed an opening within normal limits for the so-called R value in 88%; a delayed opening was measured in 6%, and rarely no opening was measured in 2%. CONCLUSIONS: TMM is a reliable tool for measuring ETF in children. The normal limit for the R value should be set at 1.12. The proposed measuring algorithm and results can be used to calculate sensitivity and specificity in a future study.