OPTIKON KERATRON ONDA, Инструкция по установке и эксплуатации

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Keratron
™
Onda Installation and operating manual
OPTIKON 2000
Cod. 161401EN 7-20
2015-03-27
Rev.C
In topo-
aberrometry the “
wavefront
” sensor image is shown next to the topography
image, thereby allowing the operator to understand whether the retinal reflection is
adequate or whether it is necessary to center the image so that the SLD band
correctly enters the pupil area. Any corneal reflections can be avoided by keeping
the vertex (center of the rings) outside of the circular zone of the SLD band
specifically indicated on the monitor (refer to the example in Figure 7-34), an area
which, in any case, must fall i
n the pupil, otherwise the reflection and the “
wavefront
sensor
” image itself vanish.
Figure 7-34: Presence of corneal reflection
7.6 TOPO-ABERROMETRY: ACQUIRED IMAGE
As soon as the topo-aberrometry is acquired, the screen shown in Figure 7-35 or
Figure 7-37 will show three images. The first to the left, taken immediately after the
LEDs light up while the pupil is still dilated, is normally used for the topography. The
second, taken after approximately 800 msec, is normally used for photopic
pupillometry. The third is the
wavefront image.
If the images are visibly moved or contain artifacts, they can be discarded
immediately by pressing [Discard] and returning to the acquisition status. Otherwise
you can process them or send them to the external PC.
During acquisition, if the patient’s eye moves too quickly away from or toward the
ideal focus point in relation to the mires cone, the software indicates the unreliability
of the acquisition by means of the message in Figure 7-35. After pressing [OK],