Zeiss HUMPHREY 720i User Manual - page 80
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TEST PARAMETERS AND STRATEGIES
REV.B 02/03 PN 51680-1
HUMPHREY FIELD ANALYZER II -
i series
Test Mode
Age Corrected
A hill of vision is assigned to the patient based
on the patient’s age. The expected threshold at the
hill’s peak, the fovea, is called the central reference
level. This central decibel value is indicated on the
test screen and the printout.
The patient’s date of birth must be entered prior to
beginning the test. Age corrected mode may only be
used with standard stimulus size and color (Size III,
White). If non-standard size and color parameters
are selected with Age Corrected Screening, the in-
strument will default back to Threshold Related
Strategy upon leaving the Change Parameter Screen.
Threshold
A hill of vision is assigned only after threshold
Related
values for 4 primary points are determined. The cal-
culated threshold at the hill’s peak, or fovea, is
called the central reference level. This value ap-
pears on the test screen and the printout.
Single Intensity
The HFA uses a default intensity level of 10 dB to test
the entire visual field. If a different intensity is de-
sired, press CLEAR and enter the desired value on
the keypad which appears. Press ENTER. The single
intensity value will appear on the test screen (as
Stim:) and on the printout as “Stimulus Intensity”.
Single Intensity levels may be set only in even
increments.
Stimulus Size
I, II, III,
Five stimulus sizes (diameters) are available on
IV, V
most instrument models. They range from Size I
(smallest) to Size V (largest). Model 720i has only
the Size III stimulus available for testing.
Stimulus Color
White
White stimulus projected onto bowl.
Red
Red stimulus projected onto bowl.
Blue
Blue stimulus projected onto bowl.
Screening
Parameter
Description
Parameters
Settings
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