otometrics madsen itera ii, Справочное руководство

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• It is recommended to use the default setup used in connection with selecting
MASK ON
for presenting the masking
signal as continuous presentation.
This means that you will not be using the
INT
button to control the masking signal.
Testing
1. Establish the unmasked bone threshold. If this has been done previously, and a different level is established in this
step, do not overwrite the previously recorded threshold. The conditions may have changed if the masking trans-
ducers were placed following the first test (for example due to the occlusion effect).
2. Press
MASK ON
to activate masking.
3. Set the masking level at the air conduction threshold of the masking ear and make sure that it is heard by the patient.
If it is not, increase the masking level.
4. Present the tone to the test ear at the previously confirmed unmasked bone conduction threshold level.
If the tone is not heard, increase the level in 5 dB steps until the patient responds.
5. When the patient responds, increase the masking level in 5 dB steps.
After each increase, present the tone no more than twice. The tone is considered heard if the patient responds at
least once.
If the tone is heard when the masking level has been increased with at least three 5 dB steps, the so called masking
plateau has been reached and the test tone level is considered the masked hearing threshold level.
6. If the tone is not heard when the masking level is increased, increase the test tone level until the tone is heard by the
patient.
Repeat from step 5 .
7. If the test tone level at the masking plateau (established in step 5 ) is within 5 dB from the unmasked threshold level,
you can skip step 8 .
8. Keep the established masking level and confirm the masked hearing threshold level. To do so:
Decrease the test tone level by 10 dB and increase in 5 dB steps.
The patient should respond within 5 dB from the previously determined masked threshold level.
If not, repeat from 3 .
9. If needed, test the remaining frequencies in the same way and switch to the other ear.
6.4 Storing thresholds
To use the store button, see Store/toggle threshold status
►
23 .
Results can be stored on a PC when MADSEN Itera II is used with the OTOsuite Audiometry module.
Otometrics - MADSEN Itera II 67
6 Tone testing