Zeiss CIRRUS HD-OCT 500, User Manual

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CIRRUS HD-OCT User Manual 2660021169012 Rev. A 2017-12
Anterior Segment
8-45
reports. Right-click a map and check Clear User Selection to clear the thickness marker you
have selected. Right-click at a location on a map to deselect Show Mean Only (the default
setting), to show only all three values per sector: Min, Max, Avg. Right-click and select
Hide Data to hide all data values on a map.
Cornea Thickness Data Tables
The data tables displayed below the pachymetry maps contain thickness measurements for
the zones on the pachymetry maps. Minimum, average, and maximum thickness
measurements in micrometers for the three radial zones appear. The zone range is defined
in millimeters away from the center of the map. The central ring has a diameter
corresponding to 2 mm, the second ring a diameter corresponding to 5 mm, and the outer
ring corresponding to a diameter of 7 mm. The zone grid is centered on the corneal vertex.
The “X” shows the location of the vertex. The white dot on each map in
Figure 8-29
shows the location of minimum corneal thickness. This value is also reported in the data
table.
The values S-I are calculated by subtracting the average value in the I sector at the
specified distance from the center, from the average value in the S sector, at the
corresponding distance.
Likewise, The values SN-SI are calculated by subtracting the average value in the SI sector
at the specified distance from the center, from the average value in the SN sector, at the
corresponding distance.
Epithelial Thickness Maps
Select the Epithelial Thickness Maps option from the View dropdown, to change the screen
so that the two thickness maps reflect values for the Corneal Epithelium alone as shown in
Figure 8-30 . This option is discussed in detail in " In Pachymetry Analysis" on page
8-51 .