Elektron Technology HENSON 8000, User Manual

Page: 37 / 159

37 Visual field tests
© 2017 Elektron Technology
3 .1 .7
C h a n g in g t h e s u p ra -t h re s h o ld in cre me n t
There are 3 different Supra-threshold test increments, 5, 8 and 12dB.
Each of the test increments has a button on the icon bar (see above). The
button that appears to be dow n gives the currently selected increment. The
increment can be changed by clicking over the required button .
Single stimulus
In the Single stimulus supra-threshold test the increment is adjusted
automatically. If a stimulus is missed the program w ill come back to the location
and re-test it at the same intensity. If it is missed a second time it w ill come
back to test it at 8dB above threshold and if missed at 8dB then at 12dB above
threshold.
Multiple stimulus
In the multiple stimulus supra-threshold test the program starts off testing at
5dB above the threshold estimate. If the patient reports less than the correct
number of stimuli then the pattern should be repeated. If they still report less
than the correct number then the patient is asked to report w here they saw
the stimuli. The perimetrist then
marks the location (s) they missed. The
perimetrist should then alter the supra-threshold increment in order to
measure the depth of the defect.
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