The Acoustic Impedance Measured on Normal and Pathological Ears: Orientating Studies on the Applicability of Impedance Measurement in Otological Diagnosis

Abstract

This is a comprehensive discussion on methods and means to find an empirical correlation between the acoustic impedance of the ear as measured at the tympanum and conductive deafness, as described in otologic terminology. The hope no doubt was that ultimately such a measurement could be perfected as a useful routine diagnostic test. The conclusion seems to be that it is still in a hopeful experimental stage. A measurement of acoustic impedance may be regarded as an extension, quantitative and qualitative, of the older tests of "mobility" of the tympanum and its surrounding appendages. Being purely an external test, it can hardly be expected by itself alone to discriminate clearly between different kinds of conductive lesions in the complex measurement beyond the drum unless it is found later that such lesions invariably follow a simple pattern. The solution of the problem of the dynamics of normal conduction through the middle