Interacoustics AA222 Instructions For Use Manual page 240

AA222 Instructions for Use – US
3.7.1.10 SISI (short increment sensitivity index)
SISI is designed to test the ability to recognize a 1dB increase in intensity during a series of bursts of pure
tones presented 20 dB above the pure tone threshold for the test frequency. It can be used to differentiate
between cochlear and retrocochlear disorders, as a patient with a cochlear disorder will be able to perceive
the increments of 1 dB, whereas a patient with a retrocochlear disorder will not. 20 measures must be
obtained in order to have the SISI threshold shown at the given frequency.
Function Key
A
B
C
Description
Amplitude Modulation (0, 1(SISI), 2, 5)
Start SISI test
Pause SISI test
Stop SISI test
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