otometrics Madsen Xeta, Справочное руководство

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• The tones may at times appear to be very weak.
• Instruct the patient in how to use the patient responder ( The patient responder ► 47 ).
• The patient should press the patient responder as soon as the tone is heard, even if it is very weak.
5.2.5 Preparing for bone conduction testing
Make sure that the bone conductor is properly connected.
Fitting the bone conductor on the patient
When you fit the bone conductor on the patient:
•
Instruct the patient in what you are about to do.
Note
•
The bone conductor cable and insert phone cable must not be removed or tampered with while
MADSEN Xeta is powered on. Either disconnect the bone conductor or insert phone entirely from the instru-
ment, or make sure that the instrument itself is disconnected from the power source.
• If a sound booth is not available, place the patient facing away from MADSEN Xeta. This is to avoid visual
clues during testing.
• If applicable, set the switch on the Talk Back microphone to ON and set the level of Talk Back.
• Position the bone conductor/vibrator so that it rests comfortably against the mastoid bone (behind the ear)
and is not in contact with the pinna, or against the patient’s forehead.
• If MADSEN Xeta is calibrated for this, see BC transducer ► 62 to choose between Forehead and Mastoid, depending
on the preferred placement of the bone conductor.
Testing with masking
If you intend to use masking, either use the mono insert phone (recommended) or fit the headphones so that the red
(right) phone is applied to the poorer ear for masking, and the other phone is applied to the patient's temple region, leav-
ing the test ear uncovered.
Important
•
The masking transducer must not under any circumstances block or cover the bone conduction test ear. If
it does, this will invalidate the test due to the occlusion effect.
Make sure that there is no contact between the headband, which holds the bone conductor in place, and the headset
or headband supporting the headphones. This will prevent vibrations from being conducted from one to the other.
Leave it in this position until the test is finished.
Instructing the patient
• The patient will be hearing brief tones.
• The tones may at times appear to be very weak.
• The tones can be heard either in the one ear, in the other ear or in both ears simultaneously.
• Instruct the patient in how to use the patient responder.
• The patient should press the patient responder as soon as the tone is heard, even if it is very weak.
• You may prefer that the patient indicates in which ear the tone was heard by raising a hand.
• The patient should not touch or move the bone conductor from its position.
48 Otometrics - MADSEN Xeta
5 Preparing for testing