Zeiss HUMPHREY 720i, Руководство пользователя

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SETTING-UP TESTS 3-7
REV. B 02/03 PN 51680-1 HUMPHREY FIELD ANALYZER
II -
i
series
Test library notes There are a number of different uses for the tests included with your HFA II. Some have special
settings or conditions that are important to understand to correctly perform the test.
• The Bottom LED fixation target is automatically used by the HFA II in order to test all
points of the Superior 36 or Superior 64 point Screening Test. Remember to direct the
patient’s fixation to this lower target. If you manually set the Central target to be used
with either Superior Field test, some of the most superior points will be omitted from
the test pattern. These tests should be run in the Single Intensity mode with the stimulus
set to 10 dB. If you use these tests often, refer to “Altering the Main Menu screen” in
Section 2 for information on how to put the test on the Main Menu with the 10 dB
stimulus permanently set.
• The Full Field 135 Screening Test will not display all tested points on the screen.
However, all points will be tested and may be viewed on the printout.
• To better view the central portion of any completed Full Field test, use the ZOOM button
located on the End of Test or View Test screen.
• Any Full Field test whose central 30 degrees have been tested, may be saved, printed
and later recalled from disk without completing the peripheral portion of the test.
• The Central 76 point test grid is identical to that of the 30-2 Central threshold test. This
allows the practitioner to follow up screening tests with threshold testing at the same
points. Similarly, the Peripheral 60 screening test has the same test pattern as the 60-4
threshold test.
• The Macula Threshold Test will test all 16 points twice if the Fluctuation feature is
turned ON. If it is turned OFF, the Macula Threshold Test will determine the threshold
once. With Fluctuation OFF, the instrument will determine the macular threshold twice
only if there is a discrepancy with expected values. The Fluctuation function may be
accessed through the Change Parameters menu screen. See Section 6: “Fluctuation
Values” or Section 7: “Global Indices” for further information.
Much like the Snellen scale for central acuity, the Esterman scale is especially useful for
evaluating visual capability or disability in industry, law, and government (workers’
compensation, motor vehicle, aviation, military). The Esterman test is listed as an option for
many disability screenings. Carl Zeiss Meditec is grateful to the American Academy of
Ophthalmology for providing the rights to offer the Esterman test for your use.
The Esterman test scores are based on a relative value scale, which is divided into unequal
units of 100 for monocular tests and 120 for binocular tests. Each unit is equated to one test
point and is given a value of 1% in the monocular field and .83% in the binocular field. The
inequality in the size and distribution of the units, with greater unit density in more important
areas, makes the scale functional. The HFA II yields the functional score automatically as a
percentage and prints it in the lower corner of the printout.
Monocular tests incorporate 100 points and extend 75 degrees temporally and 60 degrees
nasally. Binocular tests incorporate 120 points and extend 150 degrees bitemporally. Each
stimulus duration is 400 milliseconds with a single intensity Goldmann stimulus of III 4 E (10
dB). These settings have been standardized by international agreement and may not be altered
by the user. You may only change the test speed. Testing instructions are provided in Section 5.
Esterman functional tests
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