Zeiss CIRRUS HD-OCT 500, User Manual

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Tracking and Repeat Scans
2660021169012 Rev. A 2017-12 CIRRUS HD-OCT User Manual
6-32
• The OCT B-scan should be flattened to fit into all acquisition windows horizontally,
avoiding top of the window.
• A tilted retina may be corrected for by moving the pupil alignment off–center to allow
for a more level OCT scan.
• Media opacities may be minimized by searching different pupil positions for the
brightest OCT image.
For All Scans
In all cases, adjust the enhancement settings to achieve the brightest and clearest scan.
NOTE: You may see a reflection of a rectangular band over the pupil, as seen in
Figure 6-19 . This artifact has no significance.
• Review the captured data to ensure it is of acceptable quality. Besides the observed
image quality, an important element of acceptable quality is the Signal Strength
indicator, which should be 6 or higher. Signal strength and image quality can be
significantly reduced when the imaging aperture (the lens) is dirty or smudged. If you
suspect this problem, follow the instructions to clean the
"Imaging Aperture Lens
and External Lenses" on page 12-3 .
• If the captured scan is of good quality, click Save and continue. If it is not, click Try
Again to return to the Acquire screen.
• When you are finished acquiring scans, click Finish in the Acquire screen. You will
return to the ID Patient screen.
Tracking and Repeat Scans
Repeat Scans
CIRRUS HD-OCT contains automatic and manual functions to repeat scan setup and
alignment during follow–up patient visits. Repeat scans are separated into two types:
• Auto Repeat, available if you have saved the same scan type for a patient and eye on
a previous visit. These scans are specifically geared toward previous patient visits, to
reduce setup time and quickly compare macular changes that may have occurred in
the interval between visits.
• Manual Selection is geared toward same–visit repeats, when it is desirable to change
scan types, under the same conditions and settings as the previous scan.
Auto Repeat is accessed in the Tools menu of the Acquire screen Tool Bar "Toolbar
Options" on page 3-5 . When enabled, the instrument automatically adjusts the ocular
lens and chinrest to the previous settings for the same patient, eye, and acquisition scan
type. The repeated parameters include chinrest alignment, scan pattern and fixation target
placement, Enhance (polarization) and Center (z–alignment) settings, focus, brightness,
contrast, and illumination settings. These adjustments occur with the patients chin in or
out of the chinrest. It takes a few moments for the chinrest to move and all parameters to
be applied.