PRINCIPLES OF OPERATION
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D-0014930-A
– Otowave 102-C Operating Manual
In acoustic reflex testing, the 226Hz tone is used to measure the admittance of the ear, while a short tone at a
different frequency is presented (the reflex stimulus). The level of this stimulus is increased in steps until the
stapedial muscles respond, causing the tympanic membrane to become stiffer, or a preset maximum level is
reached. When the change in admittance exceeds a predetermined threshold this constitutes a reflex and the
change in admittance at that level when the stimulus is applied is displayed as a plot against time.
The stapedial reflex is measured at the static ear canal pressure that produces the maximum membrane
admittance, so reflex measurements are taken after the tympanogram is measured when the peak admittance
pressure has been established.
The reflex stimulus is produced in the ear being measured.
