of the patient's head position in real time displays on the computer monitor. (For information about setting this
option, refer to the Reference Manual.)
8.6
Gaze tests
In these tests, the goggles collect horizontal and vertical eye position data. The high speed camera captures the image of
the eye. The OTOsuite Vestibular software processes the eye position data and calculates the slow-phase velocity (SPV).
Gaze
tests provide the ability to assess for gaze and spontaneous nystagmus. The purpose of these two test types is to
identify nystagmus that is evoked without stimulus by having the patient stare at certain positions. The patient is typically
in a sitting position or in the caloric position (head inclined 30°).
Gaze
This test type assesses the patient’s eye movement when the eyes are fixated in different directions (left, right, up, down
and center). The person assessing the patient will provide the stimulus at which the patient is to stare. This stimulus can
be the tester’s finger, an implement (for example, the tip of pen or bobby pin) or the laser light presented on a wall from a
presentation remote. Or, as in the case of vision-denied testing, the patient can be verbally instructed to look into the
chosen direction. According to the ANSI standard, the eyes should be recorded for a minimum of 10 seconds with the eyes
positioned at 30° from center, right and left as well as 25° from center for up and down. In order to assess for alternating
or direction changing nystagmus the eyes should be recorded for more than 2 minutes. Please be aware that having the
patient look further than the degrees stated above can result in end-point nystagmus which is not diagnostically relevant.
The
Gaze
test may be performed with vision or with vision denied.
Spontaneous
This test type assesses the patient’s eye movement when the eyes are in the primary position looking straight ahead
without any visual stimulus. According to the ANSI standard, the eyes should be recorded for a minimum of 20 seconds.
The patient or patient's head may be in various conditions such as sitting, supine, chin to chest or head extended back-
ward. The Spontaneous test may be performed with vision or with vision denied.
8.7
Collecting Gaze data
For information about settings available in
Test Options
when collecting data, refer to the Reference Manual.
Note
•
The temporary patient is available to allow testing to start without entering any patient data. Refer to
to create a new patient or open an existing patient.
When collecting data, you can monitor head movement using the
Head Position Feedback
display or
Synchronized Room
Video
. You can also choose to not use either.(The default display is set in
Test Options
.)
Otometrics - ICS Impulse USB
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8 Oculomotor
