otometrics madsen itera ii, Справочное руководство

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• Press the
REVERSE
button to set the stimulus signal to continuous presentation (use full for placing the bone con-
ductor correctly on the patient).
• Set the dB level to a level that will be heard clearly by the patient.
• Place the bone conductor on the patient. See Preparing for bone conduction testing ► 55 .
• Find the best position for the bone conductor. Ask the patient to report when the tone seems the loudest.
• Make sure that the bone conductor stays securely in place with no contact to the pinna.
• Give the Patient Responder to the patient and explain how it should be operated (see The patient responder ► 54 ).
• Press
REVERSE
to deactivate the
REVERSE
function.
• If you want to use a predefined duration of the signal presentation when you press the
INT
button, press
IMPULSE
.
• If you wish to use masking, see Testing with masking ► 64 .
• If needed, turn the
FREQUENCY
knob to set the starting frequency: Typical starting frequency: 1000 Hz.
The signal is usually presented for each tone in the following order:
1000 Hz and increasing frequencies,
followed by
frequencies below 1000 Hz in descending order.
The typical test frequencies are:
250 Hz to 4000 Hz.
• Set the initial level of the presented signal to an audible level: Turn the
LEVEL
knob to 40 dB HL.
This is to familiarize the patient with the test signal. Other familiarization procedures may be preferred.
• If you intend to test both ears, test the better ear first. If this is unknown, start with the right ear. Press
L<-->R
to
select the ear you wish to test.
6.2.1 Testing
1. Press the INT button (right or left) to present the tone to the patient for 1 to 1.5 seconds.
2. If the patient does not respond to the presented signal, turn the
LEVEL
knob to increase the signal level in steps of
10 dB until the patient responds.
3. Reduce the signal level by 20 dB until the patient does not respond to the signal.
4. Increase the signal level in steps of 5 dB and present the signal to the patient at each level until the patient responds
to the signal.
5. Reduce the signal level by 10 dB and present signals at levels increased by 5 dB until the patient responds.
6. Repeat item 5 , 1 to 3 times until the patient has responded 3 times at the same level.
This level represents the unmasked hearing threshold at 1000 Hz based on 3-5 ascending series.
In some situations, it may be satisfactory with two responses at the same level.
If the patient has responded less than 3 times at the same level after 5 series, present a signal at 10 dB above the level
where a response was last registered.
Then repeat items 3 to 6 .
7. When the threshold is determined, press STORE to store that particular threshold. See Store/toggle threshold status
► 23 .
8. Turn the
FREQUENCY
knob to select the next frequency.
Otometrics - MADSEN Itera II 63
6 Tone testing