How to interpret the visual field printout Learn basic terms of visual field analysis How to diagnose glaucomatous field defect How to diagnose neurological field defect

1. Humphrey visual field printout ----
interpretation
Prof. Md. Shamsul Haque
SBMCH, BARISAL, BANGLADESH

2. Retinal nerve fibre arrangement
Nerve fibres arrangement at optic disc

4. What is visual field ?

5. Aims of today,s topic
Will be able
• to identify field defect
• to recognize that field defect is due to
glaucoma or neurological lesion
•to know that field defect is progressive or not

6. What is perimetry ?
Bjerrum,s screen Lister octopus
Humphrey
Goldmann

7. Types of perimetry
a. Kinetic…stimulus moves
confrontation, lister, tangen screen, Goldmann
b. Static …stimulus does not moves
HVFA, OCTOPUS
1970………OCTOPUS, Unpopular
1984………HUMPHREY, Popular

8. Advantages of Goldmann perimetry
Low vision patient
Neurological patient
Peripheral field to be evaluated
Malinger patients

9. Difference between kinetic and static
perimetry
Static Kinetic
1.VFD detect earlier with 1. Detect when 40% damage
20% defect
2. Area fixed but stimulus 2. Intensity is fixed but
varies in intensity stimulus moves from
non-seeing to seeing area
3. Three dimensional 3. Two dimensional
4. Computerized 4. Not computerized
5. Threshold type 5. Non threshold type
6. Less error 6. More error
7. Both glaucoma and 7. Good for neurological
neurological

10. Some importants terms
•Apostilbs(asb)
•Decibel(dB)
•Threshold
•Supra-threshold
•Infra-threshold

11. Apostilbs(asb) and Decibels(dB) relationship

12. •Threshold
•Suprathreshold
•Infrathreshold

13. Aposilbs, Decibels , Retinal sensitivity relation

14. Humphrey visual field test, Classification
Two types– on the basis of strategies
1. Threshold test—using threshold stimulus for
diagnosis of glaucoma and neurological lesions
2. Screening test– using suprathreshold stimulus for
detection of glaucoma

15. 1.Threshold test—is of three types
a.Central tests b.Peripheral tests c.Special tests
central 30-2 peripheral 60-4 neurological -20
central 24-2 nasal step neurological –30
central 10- 2
macular program

16. Central 30- 2 threshold test pattern
•No of test points –76
•Point density is 6° (distance between the two points)
•Bare area(non-testing area) is 3° from the fixation point
•Extension of testing area from the fixation point is 30°
NB: one eye is tested at a time,
other eye is occluded
Fixation should be steady and
monitor throughout the test

17. Central 24-2 threshold test pattern
•No. of test points---54
•Point density is 6° (distance between two points is 6°)
•Bare area (non-seeing area) is 3° from the fixation point
•Extension of testing area from fixation point is 24°

18. Central 10-2 threshold pattern
•No. of points----68
•Point density is 2°(distance between two points is 2°)
•Bare area(non-seeing area) is 1° from the fixation point
•Extension of testing area from the fixation point is 10°

19. Macular program
•No. of teat point is 16
•Point density is 2°(distance between two points is 2°)
•Bare area (non-seeing area) is 1° from the fixation point
•Extension of testing area from the fixation point is 5°

20. Why we select 30-2/24-2/10-2 central threshold test pattern
instead of 30-1/24-1/10-1
-*
Central 30-2
•No. of test points is 76
•Testing points are away from vertical
and horizontal axes
•Bare area is 3° from the fixation point
Central 30-1
•No. of test points is 71
•Testing points fall upon the vertical and
horizontal axes
•Bare area is 6° from the fixation point

21. Threshold testing strategies
Threshold testing strategies is of two types
1.Old standard strategies – full threshold strategies/standard threshold
strategies
2. Newer threshold trategies
a. FAST PAC
b. SITA standard
c. SITA fast
SITA– Swedish Interactive Threshold Algorithm

22. Humphrey visual field test printout(single
field)----interpretation
We can divide the printout into 8 zones
Zone—1, Patients data and test data
Zone—2, Foveal threshold and reliable indices
Zone—3, Gray scale
Zone—4. Patients raw data
Zone—5, Total deviation plot
Zone– 6, Pattern deviation plot
Zone—7, Global indices
Zone—8, Glaucoma hemifield test
Zone—9, Eye tracking(±)

23. Identify 8 zones of the Humphrey printout

24. Zone—1, Patients data and test data

25. Zone—2 ,Foveal threshold and reliable
indices

26. Zone—3, Gray scale
•RP
•PRP
•Peripheral retinal degeneration
•Retinoschiasis
•Aphakic glass

27. Zone—4, Patients raw data

28. Zone –5, total deviation plot,has two components
A. Total deviation numerical plot(TDNP)
B. Total deviation probability plot(TDPP)
A
B

29. Zone –6, pattern deviation plot,has two components
A.Pattern deviation numerical plot(PDNP)
B. Pattern deviation probability plot(PDPP)
A
B
•Mild to moderate generalized depression
are eliminated
•Deep focal deviations are height lighted
•Machine adjusts these values and the new
resultant values are displayed as symbolic
form in PDPP
Factors influencing the pattern deviation
plot are
•Hazy media
•Miotic pupil

30. Zone—7, Global indices
MD—mean deviation
• Indicate average severity of the field loss
• Expressed in decibel(Db) value
•Machine analyses and calculates how often these
values are seen in general population, if the value is
positive it indicates pt,s score is better than normal
person of the same age
PSD—Pattern Standard Deviation
•This is a measure of focal loss or variability within
the field
•If score is high, damage is more

31. Zone—8, Glaucoma hemifield test(GHT)
GHT
GHT→ Glaucoma Hemifield Test
Compare mirror image locations of superior
and inferior retina and gives five comments
1. GHT—outside normal limit ,if difference
found in 1% population
2. GHT—borderline , if difference found in up
to 3% population
3. GHT—abnormally low sensitive, best
sensitive part is seen in less than 5% of the
population
4. GHT—abnormally high sensitive, best
sensitive part is seen is more that found in
99.5% population
5. GHT—within normal limit, when none of
the above 4 conditions are seen

32. Zone –9, Eye tracking

33. SWAP→ Short Wave length Automated Perimetry
When and why SWAP strategies is done
•Done to detect very early glaucomatous damage
•Background colour of the machine bowl is yellow –which
desensitize the red and green cones
•Colour of the stimulus is blue which activates the blue
cones only

34. Frequency doubling technology(FDT)
•This is a latest machine
•It utilizes latest technology
•Machine is upto 97% sensitive to detect
glaucomatous defect

35. Visual field defects
•Generalized depression→ both central and peripheral
fields are depressed as in cataract
•Peripheral depression → only peripheral field is
depressed as in RP
•Temporal contraction → only temporal field is
depressed as in aging people
(Depression means reduced sensitivity of the retina)
Scotomas → non-seeing area of the visual field
Types:
•Absolute
•Relative
•Positive
•Negative

36. Cont.
•Hemifield defect
•Altitudinal field defect
•Central scotom
•Paracentral scotoma
•Centro-cecal scotoma
•Arcuate scotoma
•Nasal step
•Ring scotoma
•Macular splitting
•Bjerrum scotoma/siedel,s sign/siedel scotoma
•Baring of the blind spot

38. Take home message

39. Octopus printout

40. Dense superior scotoma originate
From BS, joins superior arcuate
scotoma and finally joins the
superior nasal step

41. By examining the gray
scale and pattern
probability plots of Right
eye and Left eye , it is
evident that this is a case
of POAG .
Right eye has tubular
vision and Left eye has a
bit more central vision
than the right eye

42. Bitemporal hemianopia : Lesion is situated at the chaisma which
damage the crossing nasal fibres of both optic nerves

43. Lesion : acute ischaemia in the frontal and parietal lobes affecting the
superior fibres of the left optic radiation causing right inferior
homonymous quardrantanopia , lesion is confirmed by MRI/MRA
Pie in the
floor

44. Pie in
the sky
Lesion: in the frontal and parietal lobes affecting the lower
fibres of the right optic radiation causing left homonymous
superior quadrantanopia –should be confirmed by MRI/MRA

45. Field of left eye
Superior altitudinal
field defect (L/E)
Causes
•AION
• Optic neuritis
• Hemiretinal vein occlusion
•Hemiretinal artery occlusion
•Optic nerve coloboma
•Glaucoma

46. Left homonymous hemianopia
Lesion: in the right temporo-parietal region affecting the
right optic radiation
MRI shows haematoma of the right temporo-parietal region