Daily tympanometry as a functional measure of middle ear status and Eustachian tube function

Abstract

Objective Tympanometry is a relatively simple method to assess middle ear (ME) status and pressure. Daily, serial tympanometric measurements may contain information on the constitutional efficiency of Eustachian tube function (ETF). A study was conducted to determine family compliance with an effort-intensive protocol that requires daily tympanometry done on each child, daily symptom recording by a parent and weekly visits with study personnel and to abstract measures that summarize the data as they relate to ETF. Methods Longitudinal 6-month, daily follow-up on 249 children from 123 families by parent-recorded bilateral tympanometry and cold-like illnesses. Results Study attrition was minimal with 90% of the enrolled families completing 90% of the study period. Parental compliance with daily tympanometry was less. Overall, 67% of the families were 80% compliant and 51% were 90% compliant. Two measures (aMEP, average middle ear pressure; vMEP, standard deviation of MEP) were evaluated for summaries of the longitudinal tympanometric results. These measures were not bilaterally independent or mutually independent and were affected by cold-burden and age. The best summary measure of constitutional ET efficiency may be a dimensional map of vMEP on aMEP with subsequent subdivision of the dimensional space into zones with functional interpretations. Conclusion Long-term studies that require daily parental recording of tympanometry and the presence/absence of cold-like illness are feasible. It is expected that compliance with the required procedures can be increased substantially by pre-selection of candidate families. Preliminary data analyses suggest that the longitudinal tympanometric data contains important information on constitutional ETF.