Guided Progression Analysis (GPA)
Humphrey Field Analyzer II-
i
series User Manual 2660021145640 A
8-12
Establishing the GPA Baseline
The Baseline is the average of two tests chosen as representative of the patient's baseline status.
Subsequent Follow-up tests are compared with these two tests in order to help you monitor the
progression of glaucomatous change. This monitoring process can be useful for determining the
effectiveness of the patient’s therapeutic regimen in slowing or halting the progression of the
disease.
GPA Baseline – Follow-up Configurations
By default, GPA selects the Baseline and Follow-up tests for you, but you can easily change the
selection. Any given exam that you wish
to print serves as a Key Exam that dictates: 1) the printed
report options, and 2) the tests included in the multi-exam reports. Multi-test reports will allow only
tests that occurred up to the date of the Key Exam and not after. Only SITA Standard and SITA Fast
tests will offer GPA reports as options. Choosing a SITA Standard Key Exam will only allow SITA
Standard and Full Threshold exams in the GPA reports, not SITA Fast exams. Choosing a SITA Fast
Key Exam will only allow SITA Fast and Full Threshold exams in the GPA reports, not SITA Standard
exams. More information on Permitted Tests for GPA are outlined in Table 8.1.
Table 8.1 Permitted Baseline–Follow-Up Configurations for GPA
If the Key Exam is: And if the Baseline Exams are: Follow-up Exams must be:
SITA Standard SITA Standard All SITA Standard
SITA Standard Full Threshold Any combination of SITA
Standar
d and Full Threshold
SITA Fast SITA Fast All SITA Fast
SITA Fast Full Threshold Any combination of SITA Fast and
Full Thre
shold
Note: GPA supports the inclusion of Central 30-2 and 24
-2 in the same analysis. GPA will analyze all
tests in this case as if they were 24-2 tests. GPA does not support FastPac tests or Central 10-2 tests
for either Baseline or Follow-up.
Default Baseline Selection Rules
GPA software will automatically select Baseline exams for
you. The oldest
two exams of the same
type are automatically selected unless there are more than 14 Follow-up exams, in which case it
selects the first pair of exams of the same strategy immediately preceding the 14 Follow-up exams.
It is critical, however, that you ensure that tests included in the Baseline are representative of the
patient’s actual Baseline status.
GPA software assists you in identifying potentially unr
eliable exams and will remove them from the
GPA analysis, as follows:
• Learning Effect: It is not
uncommon for the measured thresholds in a patient’s initial visual
field exams to be suppressed relative to subsequent exams because the patient has not yet
become proficient at taking a visual field exam. This is known as the “Learning Effect.” If the
results of a patient’s earliest selected Baseline exam indicate a significant learning effect, and
there is another exam of the same type available to use as a Baseline, then the first exam will
To Next Page
Loading...
Need help?
General
