Basics Of VF Interpretation

Question 1

When is perimetry utilized

Answer 1

Glaucoma
Neurological disease
Retinal disease

Question 2

Role of perimetry in glaucoma

Answer 2

• fundamental in diagnosis and management
• perimetric test results that reproducibly demonstrate VF loss remain the most conclusive contributor to glaucoma diagnosis
• the most precise method for quantifying glaucomatous progression remains repeated VF testing

Question 3

When do you use a SITA standard 30-2

Answer 3

Measures visual sensitivity at 76 locations within 30 degrees of fixation-the area commonly referred to as the central visual field

Question 4

When do you use SITA standard 24-2

Answer 4

The 24-2 pattern tests 54 locations and is identical to the 30-2 pattern except that most of the outermost ring of potions has been removed

Question 5

SITA-FAST 24-2

Answer 5

• the primary difference between the SITA standard and SITA fast strategies is the amount of certainty that is required before testing can be stopped
• overall effect usually is reduced testing time without loss f diagnostic information

Question 6

SITA FAST 24-2 is less tolerant of what

Answer 6

Patient mistakes and may be best used in experienced or younger patients

Question 7

Which is more difficult, SITA fast to SITA standard

Answer 7

SITA fasts presents stimuli that more often are just barely visible, and may be a more difficult test than SITA standard
-therefore SITA fast is not the preferred choice in patients expected to have difficulty with perimetric testing

Question 8

SITA-standard 10-2

Answer 8

• covers only the area within 10 degrees of fixation using a grid of test points spaced every 2 degrees
• valuable when evaluating VF loss in macular disease
• late stage glaucoma
• SITA FAST 10-2

Question 9

Testing for drug induced maculopathy

Answer 9

Good for hydroxychloroquine using patients

10-2

Question 10

Disability testing and VF

Answer 10

Some people want to be on disability, or for driving

Question 11

Retinal disease and 24-2

Answer 11

VF testing has a role in the diagnosis and management of some retinal disease,s but direct observation and imaging of the fundus usually are of a greater values
-perimetry then becomes one of many ancillary tests

Question 12

What kind of testing for visibility

Answer 12

Suprathreshold

Question 13

A test is which the only goal is to confirm that visual function is not below the normal range

Answer 13

Suprathreshold testing

• does not provide quantitative data
• are not as sensitive to early field loss as threshold tests

Question 14

Selecting a test for VF

Answer 14

-threshold testing is always a good choice, and in sopthalmic clinical settings, it is almost always to be preferred over suprathreshold screening tests

Question 15

Standard of care for patients that’s have established field loss

Answer 15

Threshold testing

Question 16

Most common VF test used

Answer 16

24-2

Question 17

Normal time for SIAT fast

Answer 17

2-5 minutes

Question 18

Time for standard Sita 24-2

Answer 18

5-7 minutes

Question 19

Why switch to a 10-2 for late stage glaucoma

Answer 19

Peripheral vision is already gone, not sense in going through the whole thing

Question 20

VF for macular disease

Answer 20

10-2

Question 21

Perimetric follow up

Answer 21

It is usually best to follow a patient over time using the same test that was used for diagnosis

Question 22

Why do we need to use the same test every time we test a patient

Answer 22

If a patient is consistently examined with the same test strategy and test pattern, then tests can be more easily compared using standardized progression analyses

Question 23

Measures the tendency of patients to press the response button even when no stimulus has actually been seen

Answer 23

False positive

Question 24

Trigger happy

Answer 24

False positive

Question 25

Most important and used of the three available reliability indices

Answer 25

False positives

Question 26

Assess patient inattention

Answer 26

False negative errors

Question 27

Help identify patients who have failed to persons to stimuli that probably should have been seen

Answer 27

False negative

Question 28

Measures patient gaze stability, whether the patient is gazing straight ahead or looking from side to side during the test

Answer 28

Fixation losses

Question 29

An automatic dual-variable gaze tracker

Answer 29

Measures gaze direction every time a stimulus is presented

Question 30

False negatives in glaucoma

Answer 30

Can be high in glaucoma even if they are paying attention

Question 31

On the gaze tracking record, lines extending upward

Answer 31

Indicates the amount of gaze error during each stimulus presentation, with full scale indicating gaze errors of 10 degrees

Question 32

On the gaze tracking record, lines extending downward

Answer 32

Indicate that’s the instrument was unsuccessful in measuring gaze direction during that particular stimulus presentation, for instance, because of a blink

Question 33

This presentation simply shows the measured decibel sensitivity at each tested point, and is the basic information upon which all the analyses and printouts are based

Answer 33

Numerical threshold sensitivities

Question 34

These highlight loss after first correcting for any overall change in the height of the hill of vision, such as that caused by cataract

Answer 34

Pattern deviation maps

Question 35

Single most useful STATPAC analysis when glaucoma is suspected

Answer 35

The pattern deviation probability plot

Question 36

Comparing total deviation and pattern deviation

Answer 36

If the two maps look more or less the same, then there is little or no generalized depression -on the other hand, a uniformly depressed total deviation map combined with a normal-looking pattern deviation map probability infdicates a cataract

Question 37

A pattern deviation map that looks more disrupted than its corresponding total deviation map

Answer 37

Often associated with a trigger happy patient who has repeatedly pressed the response button when no stimulus was seen

Question 38

Mean deviation

Answer 38

Weighted average of the values eprestned in the total deviation numerical plot, with 0 indicating no deviation from normal and larger negative values being associated with advanced field loss

Question 39

When is MD primary used for

Answer 39

Stage VF loss and as a metric for rate of change over time | -approximately 0 dB in normal and -30dB to -35 dB in extreme filed loss

Question 40

Visual field index

Answer 40

An enhancement of MD that is designed to be less affected by cataract and more sensitive to changes near the center of the field, in order to better correlate with ganglion cells loss

Question 41

Normal vision is associated with VFI clauses near _____

Answer 41

100%

Question 42

Pattern standard deviation (PSD) summarizes

Answer 42

Localized loss in a single index, which ignoring generalized depression -low in normal fields, for uniformly depressed fields and for blind fields, and is highest in moderate to advanced localized loss

Question 43

Expert system for analyzing threshold test results

Answer 43

The glaucoma hemifield test -it has been reported to detect glaucomatous VF loss with both high sensitivity and high specificity and expresses its analysis in plain language

Question 44

The single best place to look for practitioners who are not highly experienced at visual field analysis

Answer 44

Glaucoma hemifield test

Question 45

The GHT was not designed for what

Answer 45

Toe be sensitive to neurological or retinal field loss