[Parameters of normality in multifrequency tympanometry]

Multifrequency tympanometry studies consist of tympanography using probe tone frequencies ranging from 200 to 2000 Hz, improving the study of acoustic transmission through the tympano-ossicular system because then two components of admittance, conductance and susceptance, can be separated. The resonance frequency is the frequency at which mass and spring elements of the middle ear cancel each other out, leaving only the friction component. This measurement has been found to be more sensitive to the presence of pathologies that affect the tympano-ossicular system, such as otosclerosis and rheumatoid arthritis. It is necessary to know normal pattents of tympanometric parameters to improve the study of these diseases. Multifrequency tympanometry performed on 136 patients, 91 women and 45 men, age range 11-78 years. The mean resonant frequency of the middle ear was 1132.33 Hz, mean static admittance 0.76 dapa, and mean tympanometric amplitude 94.31 mmhos ac. Age showed no systematic effect of age on any of these measures in this population, and no significant association was found between static admittance or tympanometric amplitude and resonance frequency.