Lüscher test (acoustics)

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The Lüscher test is an audiometric method of ear, nose and throat medicine , with which the detectability of small volume fluctuations is examined. The test allows conclusions to be drawn about the existence of a recruitment and thus about the location of the damage in the case of sensorineural hearing loss . The test was developed by Erhard Lüscher and Josef Zwislocki in Basel and described in 1948. The test was later modified and simplified and was widely used in the form of the SISI test .

Normal difference thresholds for tone intensity changes in percent depending on the frequency for increasing tone intensities above the hearing threshold. Representation as a band, the width of which corresponds to the difference threshold in percent. 10% = 10 dB scale divisions. Position of the tape = tone intensity above the hearing threshold (after E. Lüscher and J. Zwislocki, 1948).

Investigation process

A tone audiometer equipped with an adjustable amplitude modulator is required to perform the test . In this way, intensity fluctuations of 0–60% of a tone of any frequency and intensity can be generated. Two changes in intensity are offered per second, so the tone fluctuates in volume in this rhythm. The sound is offered 40  dB above the respective hearing threshold and the slightest noticeable change in volume is sought. The examinee is asked to hold up his hand as long as volume fluctuations can be heard.

Examination result

The difference threshold is at a tone intensity of 40 dB above the hearing threshold for the normal hearing and 10–16% (4–6.5 dB) for disturbances of the sound conduction. In the case of sensorineural hearing loss of the hair cell type (cochlear sensorineural hearing loss), the difference threshold drops to below 8% if the hearing loss is more than 30 dB.

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  1. ↑ Erhard Lüscher and Josef Zwislocki: A simple method for the monaural determination of the volume compensation . In: Archives for ear, nose and larynx medicine . tape 155 , 1948, ISSN  0365-5245 , pp. 323-334 , doi : 10.1007 / BF02278320 .