Zeiss Humphrey II-i series, Руководство пользователя

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Humphrey Field Analyzer II-
i
series User Manual 2660021145640 A
STATPAC Analysis & Printing 7-5
The Glaucoma Hemifield Test
On 24-2 and 30-2 tests, the Glaucoma Hemifield Test (GHT) evaluates five zones in the superior field
and compares these zones to their mirrored zones in the inferior field. The GHT evaluates the
severity of disturbed points in each zone pair, relative to its normative database, and prints one of
these messages: WITHIN NORMAL LIMITS, OUTSIDE NORMAL LIMITS (shown as “A” in
Figure 7.1 ),
or BORDERLINE.
Figure 7.2 Superior Field Zones Used in the Glaucoma Hemifield Test
The primary aim of the GHT is to identify localized visual field loss occurring in a pattern typical of
that seen in glaucoma. It also indicates when test results show that the overall field is depressed
severely or exhibits suspiciously high sensitivity. The message GENERAL REDUCTION OF SENSITIVITY
is printed whenever the field is depressed to a level seen in fewer than 0.5% of the normal
population in the patient’s age bracket.
Similarly, when the comparison indicates abnormally high sensitivity (a level found in fewer than
0.5% of the normal population of that age), the message ABNORMALLY HIGH SENSITIVITY appears.
The GHT does not flag the case where only a few points are abnormally high, but it will catch cases
where the overall pattern of patient responses indicates a patient who is overly anxious to push the
button. It is always useful to check the false positive and false negative errors, and fixation losses as
well.
Note: The GHT is not intended for use in patients being evaluated for diseases other than glaucoma.
FastPac tests will not display the GHT result.