Diagnostic Value Of The Resonance Frequency In Middle Ear Pathologies

Objective: The primary goal of this study is to investigate the diagnostic value of the resonance frequency comparing to the standard 226 Hz tympanometry in middle ear pathologies with intact tympanic membranes.Design: The study was designed to prospectively collect 6 (7 ears) patients with surgically confirmed middle ear pathologies as the experimental group, and 35 normal ears as the control group, which were matched to the ages and genders of the experimental subjects. Standard pure-tone audiometry, 226Hz tympanometry, and multifrequency tympanometry were preformed on each ear. The results were statistically analyzed by using the SPSS 12.0.Results: Four ears were surgically confirmed as secretory otitis media, three of them showed atypic tympanograms and one showed A type tympanograms, but all with lower resonance frequencies. The differences of resonance frequencies between secretory otitis media and normal hearing groups were statistically significant. One of the two ears with otosclerosis showed a A type tympanogram and higher resonance frequency, while the other with a Ad tympanograms and lower resonance frequency. Only one ear was confirmedas absence of incus due to congenital deformity, which showed a atypictympanogram and lower resonance frequency.Conclusions: The present findings suggest that the resonant frequency maydetect middle ear pathologies which may be ignored by traditional 226 Hztympanometry. As to the patients with non-sensorineural hearing loss andintact tympanic membranes, when the 226 Hz tympanograms seem normal oratypic, the changes of resonance frequencies may provide other helpfulinformation for diagnosis.