otometrics Madsen AccuScreen PRO, User Manual

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GN Otometrics A/S 49
AccuScreen PRO User Manual Tests
If impedance values are high:
• Wait for about 2 minutes. During this time the electrodes may
connect better to the skin and so reduce the impedance values.
• Check whether the electrodes are positioned correctly.
• Check whether the ABR electrode cable and patient cables are
connected.
• Check whether the skin locations are clean.
Note:
Remember to clean skin locations for all three electrodes well
before testing.
• If required, attach new electrodes to check whether they will
reduce the impedance values.
Calibration
If the impedance values and the balance are OK, press
OK
to start
the test (LED flashes green). The acoustical stimulus is now calibrat-
ed.
Level
shows the stimulus level
Canal
shows the volume of the outer ear canal
If the values are OK, the system automatically proceeds with the
ABR test.
The ABR test
Time
shows the test duration.
ABR
shows the probability of detecting an ABR signal.
EEG
is an indication of the amplitude of the total registered po-
tential. The lower this value is, the easier the test will be. If
the electrode signals are significantly high (disturbances,
muscular artifacts) the LED flashes red. The data measured
during this time will be ignored.
These impedance values are updated and shown every 20 seconds.
The actual test is like a race between the test time and ABR:
If Time wins, the result is a REFER .