otometrics madsen itera ii, Справочное руководство

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You can link the Store and Next Frequency functions, so that the test progresses with the next frequency when you
press
STORE
. See SETUP items
►
89 .
9. Continue to use the right and/or left
LEVEL
knob to increase/decrease intensities until you have determined all
thresholds.
10. Continue to press
STORE
after each threshold is found to store that particular threshold.
11. After each threshold is determined and stored, you will notice that as you turn the
LEVEL
knob to scroll frequencies,
each stored threshold at that particular frequency will be marked by an asterisk (*) and the relevant audiogram symbol
indicating the stored threshold.
12. Repeat this procedure for the other ear.
Note
• If the difference between the air conducted threshold and the unmasked bone conduction threshold of the
same ear is 15 dB or greater, it is recommended that you retest bone conduction thresholds with masking applied
to the contralateral ear. See
Testing with masking
►
64 .
6.3 Testing with masking
To prepare the patient for masking, see Preparing for testing with masking ► 56 .
6.3.1 When is masking required?
When to use masking for Air Conduction testing
If the difference between the thresholds in the two ears is 40 dB (TDH39), or 60 dB (EAR-3A), or greater, it is recom-
mended that you test the poorer ear again with masking applied to the better ear.
If the appliance of masking is to be optimally administered without using unnecessary masking, it is recommended in the
literature not to use the one-number-fits-all 40 dB criterion for circum-aural and 55 to 60 dB criterion for insert phones.
This may cause errors, and will increase the test time, as well as increase the strain on the patient. Instead, the literature
recommends the use of frequency specific criteria that would be taken from transducer specific inter-aural attenuation
tables available from clinical studies.
1
See also
When to use masking for Bone Conduction testing
If the difference between the air conducted threshold and the unmasked bone conduction threshold of the same ear is
15 dB or greater, it is recommended that you retest bone conduction thresholds with masking applied to the contralateral
ear. See
Testing with masking ► 64 .
When to use an insert phone
Masking via insert phone is recommended. The insert phone gives less inter-aural cross talk than the TDH39 headphones.
• Use the insert phone instead of the TDH39 headphones for masking when you test the Bone Conduction threshold of
patients with much more hearing loss in one ear than in the other. This will reduce the risk of over-masking caused by
the high masking level required in the poorer ear.
1(Katz, J., Lezynski, J. (2002). Clinical Masking. In J. Katz, ed.,
Handbook of Clinical Audiology
, Williams and Wilkins, Bal-
timore.)
64 Otometrics - MADSEN Itera II
6 Tone testing