35
D-0126050 rev 1 -
270+ Operating Manual
Please note:
When two loudspeakers are connected to the device, use
LEFT
and
RIGHT
to select the
required loudspeaker.
Change the test level and frequency as usual. In order to present a test signal to one loudspeaker and a noise
signal to the other, select the
MASK
button and control the loudness with the Channel 2 rotary control.
Please note:
For recorded speech play the 1kHz calibration tone on the recorded material and follow the
calibration procedure in Appendix A.
4.10.
PERFORMING SPECIAL TESTS
4.10.1.
STENGER (TONE AUDIOMETRY)
The Stenger test is often performed to identify pseudohypacusis and malingering subjects. It is necessary to
have an audiogram done before the Stenger test can be performed.
Both ears will be stimulated simultaneously but with different intensities. The patient will be instructed to press
the response switch when a tone is heard. A normal hearing patient will always locate the sound in the ear,
which is stimulated with higher intensities.
When Stenger was selected in the
SPECIAL
menu,
BOTH
will be shown in the ear selected and also both
light rings around both Channel rotary controls will illuminate.
To start the sequence, adjust the test tone in the poorer ear to be presented at 10 to 20dB above the indicated
threshold and the test tone in the better ear to be 20dB above threshold. The signals will then be presented to
the subject via the
PRESENT
button. Further, the intensity in the poorer ear will be increased and presented
again, until the loudness is higher in the poorer ear than in the better ear.
If the patient at that point does not respond to the test signal anymore, the test result is called a
“positive
Stenger
”, indicating the patient is ignoring the stimulus on purpose. The Stenger test is called “negative
Stenger”, when the patient is still responding to the presented stimulus in the better ear.
The test can be performed at all frequencies between 0.125 to 8kHz. Use the frequency buttons to adjust the
frequency.
Please note:
Selecting the
SPECIAL
button again will stop the Stenger Test and return to the Tone
Audiometry Screen.
4.10.2.
PERFORMING ABLB
The ABLB Test (
A
lternate
B
inaural
L
oudness
B
alance), also known as the Fowler Test, is used in subjects
with a unilateral hearing loss to identify how loudness is perceived between the ears. The ABLB test is used
in conductive hearing loss to detect recruitment at frequencies where recruitment is assumed. It is necessary
to have an audiogram done before the ABLB test can be performed.
Содержание 270+
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