3.4.2.2
SISI - Short increment sensitivity index
SISI is designed to test the ability to recognize a 1 dB 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.
SISI
3.4.2.3
ABLB – Alternate Alternate Binaural Loudness Balancing (Fowler)
ABLB (Alternate Binaural Loudness Balancing) is a test to detect perceived loudness differences between
the ears. The test is designed for people with unilateral hearing loss. It serves as a possible test for
recruitment.
The test is performed at frequencies where recruitment is presumed. The same tone is presented alternately
to both ears. The intensity is fixed in the impaired ear (20 dB above pure tone threshold). The task of the
patient is to adjust the level of the better ear until the signal in the two ears is of equal intensity. Note,
however, that the test may also be performed by fixing the intensity in the normal hearing ear and having the
patient set the tone for the impaired ear. The function keys 1, 5 and 6 are available from the ABLB test
screen.
3.4.2.4
Tone in noise (Langenbeck)
For a description of the function keys in Tone in Noise please refer to the pure tone audiometry test screen.
The function of the tone in noise test is that the tone (channel 1) and noise (channel 2) are presented to the
same ear side. The function keys available for the screen is 1, 2, 5 and 6.
D-0121151-B – 2018/11
AD528 - Instructions for Use - EN
Amplitude Modulation (0, 1(SISI), 2, 5)
Reset
Start and stop the SISI test
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