[The threshold levels of the stapedius reflex depending on the relationship between the gas pressure in the external auditory meatus and the middle ear].

The objective of the present work was to detect and elucidate effects of a single factor (gas pressure) responsible for the threshold levels of stapedius reflex. It was shown that the threshold reflexes were recorded at 105 dB SPL when the gas pressure in the external auditory meatus decreased by 150-200 pPa against the atmospheric pressure and when it increased by 100-150 pPa. These effects can be accounted for by the reduced compliance of the tympanic membrane and different changes in the state of the auditory ossicles undergoing compression and tension. When entering the most comfortable stapedial reflex levels into the patient's tuning chart, an account should be taken of the maximum value of tympanic membrane compliance.