I'm an Consultant Optometrist and I have share my knowledge about how to measure visual field of human eye in brief through ppt.

1. VISUAL FIELD
Bimal Kumar Thakur
Consultant Optometrist

2. BASIC CONCEPTS
• The Visual field refers to the total area in which
objects can be seen in the side (peripheral) vision
as you focus your eyes on a central point.
Traquair's has defined the visual field as been a
hill island of vision in a sea of darkness testing
along X-Y axes of this 3 dimensional area
determines the location in the visual field and
along the Z axis identifies the visibility threshold.
• X - Y axis - kinetic perimetry
• Z axis - static perimetry.

5. Correspondence of Retina and
Visual field

6. Visual Field Test
 Confrontation Visual Field Test:-
 Perimetry:-
 Static Perimetry
 Kinetic Perimetry
 Frequency Doubling Perimetry
 Electroretinography
 Amsler Grid

7. Tangent Screen (Bjerrum Screen)
 Kinetic Perimetry
 Test field 30 degree
 Testing distance 1meter
 Gap between Lines 15 degree interval
and circle 5 degree interval

8. TERMINOLOGIES
 Threshold:- Threshold sensitivity is the
characteristics of stimuli that is perceived
50% of the times.
• Supra threshold: 95% chance a stimulus is
seen.
• Infra threshold - 5% chance a stimulus is
seen.
 Apostilb:- asb is the unit of light intensity,
related to luminance of a given test target.

9. Goldmann Perimetry
• Kinetic and Static Perimetry
• Targets on a hemispherical bowl set
33cm from patient cornea.
• Background illumination of 31.5 abs or
10 cd/sq.m
Stimulus:-
Size- 0,I,II,III,IV&V(smallest 0& largest V)
Intensity- 1,2,3,4 (Dim 1 & Bright 4)
Intensity- a,b,c,d,e( Dim a & Bright e)

10. Humphery Automated Perimetry
• HFA - II ( 700 Series ) Aspherical bowl 30 cms away
,smaller ,more ergonomic stimuli in periphery more closer
with background illumination of 31.5 abs.
• The Humphrey Field Analyzer uses a constant target size
equal to a Goldmann "III" and varies the target brightness
only. The standard field analyzer target size GOLDMANN
"III" (4 mm2) can be changed if a larger, say
GOLDMANN "V" (64 mm2) or smaller GOLDMANN "I"
(1/16 mm2) target size if needed for severely disturbed
fields or in clinical research.

11. Testing Strategies
 Original Full Threshold test
 Fastpac
 SITA(Swedish Interactive Thresholding
Algorithm) Standard.
 SITA Fast
 SITA SWAP( Short Wavelength Automated
Perimetry.

13. Basic software design
• Strategies for threshold detection –
• Intensity of the stimulus presented at a
given point is related to the normal
threshold at that stimulus site.
• Bracketing strategies to define threshold at
any point.
4-2-2 algorithm
SITA

14. INFORMATION DISPLAY

15. Automated perimetry Report for
Humphery
 Divided in to eight zone:
Zone 1: Patients information
Zone 2:Foveal threshold & Reliability indices
Reliability indices: Fixation Loss( 20%)
False positive (33%)
False Negative (33%)
Zone 3:Grey scale graph is a color coded
representation of the retinal sensitivity.
Zone 4: TD Numeric plot &TD probability plot

16. Continue…..
Zone 5:PD numeric plot &PD probability plot
Zone 6: MD, PSD,SF, CSPD, P-value and
Visual field index.
Zone 7: Glaucoma hemifield test (GHT)
Zone 8: The raw data is collected by the
machine and and consist of the retinal
sensitivity(dB values) of each point tested for
that program. Absolute scotoma is indicated
by a zero dB value.

17. Glaucoma defect with automated
perimetry- Anderson's Criteria
• Abnormal GHT
• 3 or more contiguous non-
edge points of the 30-2 field
or 3 or more cont. points of
24-2 field with a p-value of
less than 5%, out of which at
least one point has a p-value
of less than 1%.
• The CPSD should be
abnormal with a p-value of
less than 5%.

18. AMSLER GRID
 It is a diagnostic tool that aids in the detection of
visual disturbances caused by changes in
the Retina, Choroid, particularly the Macula as
well as the Optic Nerve, Orbit, Anterior Visual
System and the visual pathway to the brain and
Cortex.
 The Grid Chart evaluate the central 20 degree of
visual field.
 There are 7 Charts, each consisting of 10 cm.sq.

19. CHART- 1
 This is merely a grid pattern consisting of
0.5cm white squares, each corresponding to
1 degree of visual field, set against a black
background.
 This is arranged in 20 horizontal & vertical
rows making 20 squares each.

20. CHART -2
 The patient with a central scotoma may
respond better if this chart is used.
 The only difference between this and
Standard grid chart is that diagonal lines
intersect at the center of the grid to form an
‘X’.

21. CHART-3
 The patient suspected of
having a Central or
Cecocentral Scotoma
associated with Nutritional
Amblyopia, as from
alcohol-related Thiamine
deficiency, or Toxic
Maculopathy, as from
Quinine and its
derivatives, should be
tested with this chart.
 This chart can also be used to differentiate patient with
functional vision loss , as from malingering with the
conjunction of red-green lenses, the red grid artificial
monocular field/vision loss may allow detection of.

22. CHART-4
 Amsler hoped that the patient with one or more paracentral
scotomas may be able to delineate the areas of
involvement more easily with this chart.
 But its credibility is doubtful since the background and
scotoma use to appear same in color for the observer may
result in false results

23. CHART -5
 This design makes it possible to rotate the chart to
any meridian to check for irregularities in a
particular/specific area.
 The patient with central or paracentral
metamorphopsia resulting from various retinal and
choroidal disorders may be especially sensitive to
this chart

24. CHART-6
 It contains black lines against a white background
and the areas 1 degree above and below the
fixation dot are bisected by additional horizontal
lines.
 Metamorphopsia along the reading level may be
more easily observed with this chart.

25. CHART-7
 This chart breaks the horizontally oriented 6 degree X 8
degree central area, which corresponds anatomically to the
normal macula, into 0.5 degree squares, rather than 1
degree squares.
 This chart is more useful in cases where there is a subtle
visual disturbance from macular disease, especially early
in the course of the disease