Ecleris VNG Plus - Care and Maintenance Procedures; General Cleaning Precautions and Methods; Console and Receiver Bar Cleaning; Goggles Cleaning and Maintenance

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APENDIX
ABNORMALITY THRESHOLD
TEST
ABNORMALITY
SIGNIFICANCE
SPONTANEOUS
Nystagmus: slow
component, followed by
fast component.
Bilateral gaze
Nystagmus: eyes open
and looking to right or
left.
2 Beats (horizontal) in 5
sec. with average velocity
of >6 deg/sec.
CNS: Nystagmus in all
gaze directions or
direction changing
Nystagmus in same
gaze direction.
SPONTANEOUS
NYSTAGMUS: CNS
(brain stem)
PVS: direction-fixed,
horizontal, or torsional
Nystagmus. Inhibited
by fixation, follows
Alexander’s law.* rule
out drugs, lack of
alertness
SMOOTH PURSUIT/
Gain: eye velocity/target
velocity
Phase: lag or lead of
eye relative to target.
Asymmetry: right gain –
left gain
Gain:
Age 50 and under: <70%
or
>140%
Age 60 – 69:
<65% or > 145%
Age 70 – 79 :
<60% or > 150%
Age 80 – 89 :
<55% or > 155%
Low gain in one
direction: CNS lesion.
Marked saccadic
pursuit:(stair step
tracking) CNS lesion