Impedance Check Button; Test Procedure And Instruction Of Patient; Insertion Of Eartips - Interacoustics Eclipse Additional Information

Eclipse Additional Information

5.11.4 Impedance check button

IMP button
1. After having attached the electrodes to the patient, it is crucial to check if the skin impedance is accepta-
ble. For best results, impedance at each electrode site should be as low as possible; preferably 10kΩ or
less and best if they are balanced.
2. To check the electrode impedances, press down the IMP button on the Preamplifier. When activated the
IMP button starts to flash.
3. Turn the dial fully clockwise and then turn it slowly counter clockwise. Each LED will turn from Red to
Green when the impedance is found for that specific electrode. The impedance value can be read on the
Preamplifier. Low and balanced electrode impedances are typically more efficient in reducing interfer-
ence.
4. If the impedance of one or more electrodes is too high, consider rechecking the bond between the skin
and electrode. If this does not help you may need to remove the electrode and repeat the skin preparation
procedure using a new electrode.
5. Return to recording mode by pressing down the IMP button again. All Preamplifier LEDs turn off.

5.11.5 Test procedure and Instruction of Patient

The oVEMP is recorded with contracted inferior oblique (eye) muscles. Therefore, the patient should be in-
structed in ways to contact the inferior oblique muscle throughout the recording. The patient is typically asked
to look upward and hold their gaze at a fixed point during recording.
 Placing a static visual target on the wall or ceiling for the patient to look at during testing will ensure con-
sistent activation of the inferior oblique muscle.
 The target should be placed at a 35 degree angle relative to the patient's neutral eye position (Kantner et
al, 2014).
 The patient can be seated or in a semi-recumbent position or lying down on e.g. an examination table
with the head elevated. Optimally the head is positioned at the same place for all test subjects, this en-
sures that the target has the same angle for each test.
 Instruct the patient to look and hold their gaze at the target without moving their head when you start the
test. The gaze of the eyes is important to maintain throughout the test, and it is therefore important that
the clinician observes the subject during recording and this way ensures symmetric muscle tonus for both
eyes, prior to the oVEMP response.
 The EMG monitor is displayed, but has no function related to the oVEMP test.
The oVEMP response is a contraction of the eye muscle and not relaxation of the contracted SCM mus-
cle (cVEMP).
Make sure that the patient understands the test procedure prior to staring the test.

5.11.6 Insertion of eartips

1. Make sure that the end of the black tube is not covered by the yellow foam when you roll the tip into the
smallest diameter possible.
2. Insert the tip well into the ear canal. The correct insertion depth into the ear canal is obtained when the
rear edge of the tip is 2-3 mm inside the entrance of the ear canal.
3. Secure the tip in the ear canal until foam expands.
Use a new pair of ear tips for the next patient.
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