otometrics madsen itera ii, Reference Manual

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Hz dB Source
6000 44 Munro & Agnew, BJA (1999)
8000 42 Munro & Agnew, BJA (1999)
6.3.2 Air conduction with masking - suggested procedure
Prerequisites
The unmasked hearing thresholds have first been determined as described in Air Conduction threshold test
►
61 .
Prerequisites as in Air Conduction threshold test ► 61 .
• Prepare the patient for testing with masking. See Preparing for testing with masking
►
56 .
• 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. Press
MASK ON
to activate contralateral masking.
2. Set the masking level at the threshold of the masking ear and make sure that it is heard by the patient.
If it is not, increase the masking level.
3. Present the tone to the test ear at the unmasked threshold level.
If the tone is not heard, increase the level in 5 dB steps until the patient responds.
4. 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.
5. 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 4 .
6. If the test tone level at the masking plateau (established in step 4 ) is within 5 dB from the unmasked threshold level,
you can skip step 7 .
7. 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 step 2 .
8. If required, test the remaining frequencies in the same way and switch to the other ear.
6.3.3 Bone conduction with masking - suggested procedure
Prerequisites
Prerequisites as in Bone Conduction threshold test
►
62 .
• Prepare the patient for testing with masking. See Preparing for testing with masking ► 56 .
66 Otometrics - MADSEN Itera II
6 Tone testing