Stapedial muscle reflex contraction examination - using acoustic impedance measurement under test sound before and after stimulus application (DK 22.8.77)

摘要

The system is for the examination of the reflex contraction of the stapedial muscle when the ear is stimulated, by measuring the variation in acoustic impedance of the middle ear. The acoustic impedance of the ear examined is measured by means of a test sound. The ear is stimulated and a further impedance measurement made during the rest period after the stimulus has ceased. The two measurements are compared and a signal is produced if they differ. The measurement made can be that of the acoustic elasticity and the auditory passage can be sealed hermetically before the measurements are made. The air pressure for the elasticity measurements can be set to a value corresponding to maximum elasticity.