Monitoring Eye And Head Movement - otometrics ICS Impulse USB User Manual

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Monitoring eye and head movement

While performing the head impulse test, both the
eye traces to assist you in understanding the quality of data being collected.
Real Time Trace window
This window allows you to monitor both head and eye movement while performing the head impulse test. The type of
impulse selected (Lateral, LARP, or RALP) determines which head trace is bold. The bold head trace should be the one
moving when the head impulse is delivered. The other two head traces should be fairly flat. This ensures that the canal
stimulated is the one you intended to test. During the test, the maximum sample rate is 250 samples per second.
Operator feedback is also displayed for the current impulse:
• A green circle indicates that the head impulse was delivered adequately.
• An orange circle indicates that the head impulse was not properly delivered. A message displays in the collection win-
dow alerting you to one of these errors: the impulse was too slow, there was too much overshoot in the impulse, or
wrong planes were stimulated when performing the LARP or RALP test.
If you prefer not to display the operator feedback during collection, refer to the Reference Manual.
Impulse window
In this window, the gray training lines represent the shape of good head impulses at a variety of velocities: 100, 150, 200,
and 250. The shape of the training curves changes based on the type of impulse selected (Lateral, LARP, RALP). The head
trace displayed in orange and with negative velocities represents movement to the right. The head trace displayed in blue
and with positive velocities represents movement to the left.
The actual head and eye traces are superimposed on top of the gray training lines. The eye trace is represented in green.
White dots display along the Y axis to indicate the velocities of impulses collected.
Otometrics - ICS Impulse USB
Real Time Trace
window and the
Impulse
window display head and
User Guide
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