Interactions among tympanometric variables.

R H Margolis; G R Popelka

doi:10.1044/jshr.2003.447

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PubMed · 904307

Interactions among tympanometric variables.

R H Margolis·G R Popelka

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Abstract

To gain a better understanding of tympanometric results that have been difficult to interpret, such as asymmetrical and W-shaped tympanograms, acoustic susceptance and conductance tympanograms were measured from subjects with normal hearing and from subjects with well-defined middle ear pathology. Acoustic reactance, resistance, and impedance were computed and predicted from the measured data. Asymmetrical tympanograms derive in large part from the marked asymmetry in acoustic resistance as a function of ear canal pressure. W-shaped tympanograms result from interactions between reactance and resistance that occur when the two quantities assume similar absolute values or when reactance is mass controlled. A criterion for distinguishing between W-shaped tympanograms that are normal from those that are abnormal is discussed.

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Acoustic Impedance Tests Acoustic Stimulation Atrophy Ear Canal Ear Diseases Ear Ossicles Ear, Middle Humans Pressure Tympanic Membrane Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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R H Margolis, G R Popelka. 1977. Interactions among tympanometric variables.. https://doi.org/10.1044/jshr.2003.447

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