Distribution Of Normals - Zeiss CIRRUS HD-OCT 500 User Manual

A-16
Measurement Matched to
Normal Based On
RNFL
Average RNFL Age
Thickness,
RNFL Symmetry,
RNFL Clock Hours,
RNFL Quadrants,
RNFL Thickness
(graph)
Optic Nerve Head
Rim Area and Disc Area and Age ONH Normative
Neuroretinal Rim
Thickness (graph)
Average C/D Ratio,
Vertical C/D Ratio,
Cup Volume
2660021169012 Rev. A 2017-12
Appendix

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.
Grey White
Grey shading does The thickest 5% of
not apply to RNFL measurements fall
measurements in the white area
(white > 95%).
The largest 5% of
Database is not measurements fall
applicable if: in the white area
(white > 95%).
1) The disc area is
larger than 2.5
2
mm or smaller
2
than 1.33 mm , or
2) The Average or
The smallest 5%
Vertical C/D Ratio
of measurements
is below 0.25, or
fall in the white
3) The ONH
area
Normative
(white > 95%).
Database license
has not been
activated.
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
hovers over this icon button, the tooltip appears as shown below.
Green Yellow
90% of The thinnest 5%
measurements fall of measurements
in the green area fall in the yellow
(5% < green area or below
≤
95%). (1% < yellow
5%, suspect).
90% of The smallest 5%
measurements fall of measurements
in the green area fall in the yellow
(5% < green area or below
≤
95%). (1% < yellow
5%, suspect).
90% of The largest 5% of
measurements fall measurements fall
in the green area in the yellow area
(5% < green or below
≤
95%). (1% < yellow
5%, suspect).
displays. When your cursor
CIRRUS HD-OCT User Manual
Red
The thinnest 1%
of measurements.
Measurements in
red are considered
≤ outside normal
limits
(red 1%, outside
≤
normal limits).
The smallest 1%
of measurements.
Measurements in
red are considered
outside normal
≤
limits
(red 1%, outside
≤
normal limits).
The largest 1% of
measurements.
Measurements in
red are considered
outside normal
≤
limits
(red 1%, outside
≤
normal limits).