Zeiss HUMPHREY 720i User Manual - page 57

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

3.htp

3/14/03, 3:07 PM

7