Zeiss CIRRUS HD-OCT 500, User Manual

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Appendix
2660021169012 Rev. A 2017-12 CIRRUS HD-OCT User Manual
A-16
Distribution of Normals
The gray color, shown in the legend to the left, represents “Not applicable”. Values will be
shown in gray when normative data is not applicable because the database has insufficient
data to match with the disc area.
The Distribution of Normals color scheme is used for both the RNFL and the Optic Nerve
Head analysis parameters. The table below clarifies how the color scheme is used for each
of the parameters.
NOTE: For patients under 18 years old, the legend and color coding is not displayed. Data
was not collected from patients under 18 years old.
There is measurement variability for the retinal nerve fiber layer and optic nerve head
parameters which may impact the normative database color coding. If the true value is
near the limit of what the software uses to determine the normative database color code,
then it is possible that the color code could vary from exam to exam. When at least one
parameter is close to a normative limit, a blue icon button
displays. When your cursor
hovers over this icon button, the tooltip appears as shown below.
Measurement Matched to
Normal Based On Grey White Green Yellow Red
RNFL
Average RNFL
Thickness,
RNFL Symmetry,
RNFL Clock Hours,
RNFL Quadrants,
RNFL Thickness
(graph) Age Grey shading does
not apply to RNFL
measurements The thickest 5% of
measurements fall
in the white area
(white > 95%). 90% of
measurements fall
in the green area
(5% < green
≤
95%).
The thinnest 5%
of measurements
fall in the yellow
area or below
(1% < yellow
≤
5%, suspect).
The thinnest 1%
of measurements.
Measurements in
red are considered
outside normal
limits
(red
≤
1%, outside
normal limits).
Optic Nerve Head
Rim Area and
Neuroretinal Rim
Thickness (graph) Disc Area and Age ONH Normative
Database is not
applicable if:
1) The disc area is
larger than 2.5
mm
2
or smaller
than 1.33 mm
2
, or
2) The Average or
Vertical C/D Ratio
is below 0.25, or
3) The ONH
Normative
Database license
has not been
activated.
The largest 5% of
measurements fall
in the white area
(white > 95%). 90% of
measurements fall
in the green area
(5% < green
≤
95%).
The smallest 5%
of measurements
fall in the yellow
area or below
(1% < yellow
≤
5%, suspect).
The smallest 1%
of measurements.
Measurements in
red are considered
outside normal
limits
(red
≤
1%, outside
normal limits).
Average C/D Ratio,
Vertical C/D Ratio,
Cup Volume The smallest 5%
of measurements
fall in the white
area
(white > 95%). 90% of
measurements fall
in the green area
(5% < green
≤
95%).
The largest 5% of
measurements fall
in the yellow area
or below
(1% < yellow
≤
5%, suspect).
The largest 1% of
measurements.
Measurements in
red are considered
outside normal
limits
(red
≤ 1%, outside
normal limits).