Hearing Screening Systems (Technical Manual)
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After the stimulus intensity tuning, the device switches to TEOAE registration mode.
The window displayed in this mode is given in the Fig. 17.
Fig. 17. TEOAE test window (2).
The top part of the window represents the shape of the averaged response, the left
bottom one displays its spectrum. The color gamma depends on the selected ear: the
blue one is for the left ear, the red one is for the right ear. The two curves of response
(A and B) are displayed. Their coincidence testifies of the OAE presence, their
difference shows the level of the residual noise. The response spectrum has two
areas: the dark one represents the noise level, the light one represents the response
level in those areas where it exceeds the noise level. The message “Acquisition”
appears on the information panel.
Besides, the following information is displayed here:
The number of the averaged responses/number of artifacts is located against the
“Stim./Art.” label. The big number of artifacts indicates either the strong external
acoustic noise or bad probe fitting. When the number of artifacts exceeds the
specified number of averaging (1000 by default), the message “Too much noise”
appears on the screen. In this case the test should be repeated in calmer
conditions or after the reinstallation of a probe.
Stimulus stability is against the “Stability” label. The ideal variant is when it is
equal to ”1”. The stability lesser than 0.9 indicates that the probe changed
considerably its position during the registration process. If OAE was not detected
at that, i.e. the “REFER” signature appeared on the information panel after the
test termination, repeat the test after the probe resetting; at that follow the probe
position. It should be stable.
The level of the averaged response, in dB SPL is opposite the “A&B” label. It is
the reference information about the total OAE amplitude in case the A&B value
