Elektron Technology HENSON 8000, Руководство пользователя

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31 Visual field tests
© 2017 Elektron Technology
3 .1 .3
Se t t in g t h e t e s t in t e n s it y
The Supra-threshold tests present stimuli at intensities that are above the
patients estimated threshold. It uses one of 2 techniques to establish a
patients threshold:
Age related.
The level is simply set by the age of the patient. This is
the fastest method but can lead to errors w hen a patient's threshold
departs from the average value for their age, e.g. w hen there are media
opacities.
Thresho ld related.
The level is set by a series of measurements
taken at the onset of the test. The algorithm is different for Single
and Multiple stimulus tests.
When your machine w as installed one of these techniques w ould have been
set as the default method, i.e. the method first selected w hen a supra-
threshold test is undertaken. You can change the default method w ithin the
Options program.
You can also opt to change the method at the onset of a test. For example, you
might w ant to regularly use the age setting method but then for a particular
patient, maybe one w ho has a cataract, w ant to set it according to their
threshold.
To select a different method at the onset of a test:
1. Click on the tool bar.
2. Select a method from the popup screen, see below , and then click OK.
No tes:
You can set the threshold to a given value. You might w ant to do this to
match a previous setting.
The perimeter w ill revert to the default method w hen sw apping to the
next eye or starting a new patient.
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