D-0134090-A – 2022/11
VisualEyes™ - Instructions for Use - EN
Page
81
Performing the tests
This section contains a short description on how to perform the tests available with the VisualEyes™ system.
For a detailed description, please refer to
Additional Information
.
3.9.1 VisualEyes™ 505, VisualEyes™ 515 and VisualEyes™ 525
3.9.1.1 Video Frenzel
The Video Frenzel test is available with
VisualEyes™
505
and
VisualEyes™ 525
. Video Frenzel is a basic
test, which can record patient eye movement without any analytical assessments. There is no time limit for
eye recording in this test and there is no calibration requirement to perform this test. This is generally used
for manual analysis.
3.9.1.2 Spontaneous Nystagmus
Spontaneous Nystagmus is available with all VisualEyes™ systems.
This is a vision-denied test and the
patient will look straight ahead with the goggle cover on. The operator will be able to watch the patient’s eyes
either from the computer screen or from the TV or projector screen. When the test is started, the eye
position graphs will be displayed. Nystagmus beats will be marked with triangles displayed at the onset of the
fast phase. When significant nystagmus is detected, the average slow phase velocity (a.SPV) will be
displayed in the bar graph on the right side of the eye position recordings. When the test ends, the software
will color-code the nystagmus slow phase velocities in green.
3.9.1.3 Dix Hallpike
The dedicated Dix Hallpike test is available with
VisualEyes™
515
and
VisualEyes™ 525.
This is a
vision-denied test and the test can be performed on an examination table/reclining chair. With the patient
seated in the upright reclining chair, remove the Orion or System 2000 head support and set it aside. Unlock
the chair with the ELM button (Orion) or release the foot brake (System 2000) and rotate the chair as needed
to allow the chair and patient to be fully reclined (refer to
Figure 3.9-1). Have the patient unfasten the
seatbelt. When maneuvering the patient into the standard Dix Hallpike body position, the head will hang past
the chair frame supported by the examiner. Position the patient (depending on patient height) so the patient’s
head will hang while supported off the end of the chair. If comfortable, keep the patient seated with his/her
feet off on either side of the exam chair for balance. Use the recline handle to recline the chair to be supine.
The patient will look straight ahead with the goggle cover on in a vision-denied condition. Lower the patient
into the Dix Hallpike position while supporting the head and the goggles in place. Use the RF remote, foot
pedal, or side switch to start recording the eye movements. A double beep will sound when the test is
scheduled to raise the patient back up to a sitting position. Using the RF remote, foot pedal, or side switch
will end the supine portion early and play the double beep and allow the operator to finish the test earlier if
desired.
It is also possible to add the advanced version of the test with the VORTEQ™ Assessment bundle available
for
VisualEyes™
505
,
VisualEyes™
515,
and
VisualEyes™ 525.
This includes feedback to the clinician
regarding correct head position, and recording of torsional eye movement. Refer to section 1.1.1 for further
information of the
Dix Hallpike Advanced
test.
