Zeiss CIRRUS HD-OCT 500, Руководство пользователя

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CIRRUS HD-OCT User Manual 2660021169012 Rev. A 2017-12
Specialized and Integrative Visualization Tools
8-69
The viewports are interactive: Click and drag the triangles or click a scan viewport and use
the mouse scroll wheel to “move through” the active plane of the viewport; you will see the
resulting cross–sections update simultaneously in the other viewports. This functionality
enables you to quickly search through the data cube and stop when you see an area of
interest.
Retinal Layers Automatically Detected and Displayed
Cube scan analyses incorporate an algorithm to automatically find and display the inner
limiting membrane (ILM) and the retinal pigment epithelium (RPE). CIRRUS also calculates
and presents a layer called RPEfit, which is a representation of a normal parabolic RPE for
this eye, based on the retina’s overall curvature. You can use the RPEfit line to view
variations from normal in the actual RPE contour.
In the scan images, which are cross–sections (slices), the layers appear as colored lines
that trace the anatomical feature on which they are based. The ILM is represented by a
white line, the RPE by a black line, and the RPEfit line is magenta in color. These lines are
also known as segmentation lines. You can customize the colors used to display each of
these lines, as explained below. These layers serve as the basis for the macular thickness
and volume measurements ("
Macular Thickness Analysis" on page 8-6 ), the ILM
and RPE layers are presented in their entirety as three–dimensional surface maps.
Fundus Image Overlay Options
Use the Overlay drop–down menu to select which overlay to use on the fundus image:
None (default), Slice, OCT Fundus, Slab, ILM – RPE, ILM – RPEfit, or RPE – RPEfit. The slice
and slab options correspond to the
en face
image in the lower right viewport. (The options
ILM, RPE, and RPEfit are variations of the slab. See " Slice and Slab Options" on page
8-70 ). You can adjust the associated Transparency slider from 0% (opaque) to 100% (fully
transparent). The OCT Fundus option is the same overlay (
en face
) shown on the fundus
image in the Review screen.