Interacoustics AA222 Additional Information page 33

AA222 Additional Information
4.2.2.5 Eustachian tube function – non-perforated eardrum
Make sure that you select the test labeled as Non-perforated from the list of tests on the left of the screen.
The Eustachian tube function test for the non-perforated eardrum, or ETF 1, or Williams procedure, is set up to
measure three tympanograms. It keeps the pressure between the first and second tympanograms at the Start
pressure, and between the second and third tympanograms at the Stop pressure. After testing, the pressure is
brought back to 0daPa. In between all tympanograms, a message informs you as to which instruction you
should give to the patient. The original Williams procedure asks the patient to swallow in between the different
tympanograms. Our advice is to ask the patient to perform the Valsalva maneuver after the first tympanogram
and to swallow after the second tympanogram, because the expected deviations of the peak pressure will then
be larger.
By rotating the wheel you can select and change the following settings.
Auto run. When enabled, the test will run automatically as part of the protocol.
A
While selecting this instruction, press the
alter the instruction that is shown in between the first and second tympanograms. Connect a pc
B
keyboard to the USB port of the AA222 for easy typing options, including the use of special
characters.
While selecting this instruction, press the
alter the instruction that is shown in between the second and third tympanograms. Connect a pc
C
keyboard to the USB port of the AA222 for easy typing options, including the use of special
characters.
D Start pressure. You can set the start pressure for the three automated tympanograms here. The
start pressure can vary between +400 and -600 daPa.
E Stop pressure. You can set the stop pressure for the three automated tympanograms here. The
stop pressure can vary between +300 and -600 daPa.
Pump speed. You can select the pump speed for automated tympanometry here. The stated
F
pump speeds are dependent on the size of the ear canal or cavity that is being used during the
measurement. The numbers below are therefore rough estimates.
• Automatic, is the high pump speed which automatically slows down to low pump speed
around the peak of the tympanogram. We recommend using this setting for screening and
normal tympanometry tests
button to open a pop-up in which you can
button to open a pop-up in which you can
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