Zeiss CIRRUS HD-OCT 500, Руководство пользователя

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CIRRUS HD-OCT User Manual 2660021169012 Rev. A 2017-12
Quality Check Tools
7-3
All scans should be carefully reviewed and accepted only if the quality of the scans fulfills
the requirements of the analyses for which the data was required. Tools are provided that
allow you to enhance the images, where feasible. These tools and the criteria for
acceptance are described in the following sections.
Quality Check Tools
As in scan acquisition screens, you can adjust the brightness/contrast manually ( ) or
automatically ( ) on the image in the Fundus Viewport for cube scans. Also for cube
scans, you can use the Fovea Finder ( ) to automatically center on the image Fovea,
and the transparency can be adjusted for scans based on prior images. Click to
switch the image display between color and grayscale modes.
NOTE: You can switch between color and grayscale globally, for all viewports, by selecting
or deselecting Colored OCT in the Tools menu (or by pressing F9 on the keyboard). Colored
OCT is the default.
As in all other data screens you can select to reset the image display to its default
settings.
To assist in scan review, the scan signal strength of Posterior Segment scans is displayed on
a scale of 0 to 10, with 10 being maximum. Signal strength values less than 6 are generally
unacceptable. In these cases the indicator color will be red. For signal strengths of 6 or
higher, the signal strength is acceptable, and the indicator color will be green. Click the
Information button
for additional suggestions on how to obtain better signal strength.
NOTE: The Scan Quality Check Screen for Anterior Segment scans does not show the Signal
Strength indicator.
For FastTrac scans, in addition to Signal Strength, there is a quality rating for the acquired
scan called the “Fundus Image Quality” score. A Fundus Image Quality score 6 or above
confirms that the quality is satisfactory to be used for a future scan.
A green dot ( ) in Tracked during scan indicates tracking was successful during the
scan, while a green dot ( ) in Tracked to prior indicates tracking to a prior scan was
successful.
Select to obtain additional information on the prior scan.
Double-click any image on a Scan Quality Screen to open it in full screen mode. Double–
click again to return to normal view.
During quality check, the cube scan slice locators used in scan acquisition become slice
navigators which can be repositioned to allow you to move through scan slices. Either drag
the blue or magenta triangle at the end of either cross-hair in the Fundus Viewport, or click
a scan viewport and use the mouse scroll wheel to move through the active plane of the
scan. The resulting cross–sections update simultaneously in the other viewports.