Diagnostic significance of special hearing test by using discriminant analysis in patients with cerebral apoplexy

Abstract

A great progress has been made recently in the diagnosis of the retrocochlear deafness by the supraliminal hearing test and the binaural audiometric test. We diagnosed the retrocochlear deafness by the special hearing tests performed at the Kanto Rosai Hospital. In this paper, the data for the function of the central auditory pathway in patients with cerebral apoplexy and in normal hearing persons are to be analysed by means of the discriminant function by age-groups. Of 302 subjects, 229 cases are apoplectic patients, 73 cases with normal hearing. The results of the special hearing tests were subjected to the discriminant analysis. The results were as follows: 1) The coefficient and discriminant point to classify the data for each item of the special hearing tests and the rate of misclassincation were clarified. 2) The probability of misclassification decreased in inverse proportion to the number of the test items. 3) The probability of misclassification in the middle-aged group (30 to 40 years of age) was the lowest of all age-groups. 4) The patients suspicious of the disorder of the central auditory pathway could be diagnosed and classified correctly from the data of each item of the special hearing tests, analysed by means of the discriminant function. Currently even the experts find it difficult to diagnose the disorder of the central auditory pathway, and to determine the affected site of the brain from the mere results of the special hearing tests. However, the integral judgment of the data of the special hearing tests with the introduction of the discriminant function would certainly make it easy and accurate for either experts or non-experts to recognize the disorder of the central auditory pathway. © 1978, The Oto-Rhino-Laryngological Society of Japan, Inc. All rights reserved.