Operating Instructions MI 34 / MI 34 H
GEBAmi34e.11a.docx
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850 232/14 08/11
Figure 21 Example of a normal Tympanogram with ipsilateral
reflex results
Right
Status
READY
ml
3
2
1
0
-600
-300
300 daPa
Ear Volume
Compliance
Pressure
Impedance
Gradient
0.94 ml
0.81 ml
- 37 daPa
32 daPa
Ipsi
1
2
3
4
500 Hz I
1000 Hz I
2000 Hz I
4000 Hz I
dB
100
100
100
100
PASS
PASS
PASS
PASS
AUTO
Scale
level and maximum level (see
12.3 Reflex pre-settings
). If you have
chosen a fixed level the instrument measures only with this level.
Control if the auditory canal is free.
Choose the right ear tip according to the size of the auditory canal and put
it firmly onto the probe tip.
6.4 Doing the ipsilateral measurement
Carry out the measurement
as described in chapter 4.4
“Recording the
Tympanogram”. The
Stapedius reflex is measured
after the measurement of the
Tympanogram. During the
measurement of the
Stapedius reflex the change
of the compliance is
represented in real time on
the LCD display
Ç
. When the
test is finished the curves for
the changes of compliance
for 500 Hz, 1000 Hz, 2000
Hz and 4000 Hz are shown in
four separate graphs at the
bottom of the measurement screen (see Figure 21). Below each curve you
see the test level where a Stapedius reflex was registered automatically. This
is indicated by a “PASS” below the frequency. If no reflex was detected, a
“FAIL” is reported and the maximum level is shown.
You can judge watching the real time graph if you have a “real” Stapedius
reflex or only disturbance and artifacts. The lower dotted zero-line of a
graph indicates the measured compliance without a test sound. All the
positive or negative changes of compliance are shown as deviation from the
zero-line. If a Stapedius reflex occurs the compliance decreases and the
curve rises. The box which occurs during the test symbolizes the threshold
at which the MI 34 accepts a change of compliance as valid Stapedius
reflex.
