from grand round of ophthalmic department-Al Zhraa university hospital (Dr. Jihan Abdallah, lect. of ophth.)

1. Field of vision
Jihan Abdallah
1

2. The normal extent of field of vision
60°nasally.
 50°superiorly
 70°inferiorly .
 90° temporally
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3. VISUAL FIELD
• Visual sensitivity is greatest at the very center of
the field and decreases toward the periphery.
• The part of environment where in a steadily
fixating eye can detect visual stimulus.
• Photoreceptors and corresponding visual
pathways upto the periphery of retina away from
point of fixation.
• Reflects topographic sensitivity of various foci on
retina and corresponding visual apparatus.
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4. Factors affectin`g field of vision
1-Vision
2-Refractive status
3-Education , attentiveness, cooperation
4-real size of spots
5-distance from eye
6-Duration of stimulus
7-Background illumination
8-Stimulus intensity
9-Contrast
10-Colour
11-Patient factors
12-Light / dark adaptation
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5. PHYSIOLOGICAL BLIND SPOT
Corresponding to optic nerve head
15 deg temporal to point of fixation
Span – 5 deg horizontal
-- 7 deg vertical
Two thirds below the horizontal
meridian
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6. VISUAL FIELD DEFECTS
• Scotoma - this is a type of visual field defect. It
is a defect surrounded by normal visual field.
Relative scotoma - an area where objects of
low luminance cannot be seen but larger or
brighter ones can.
Absolute scotoma - nothing can be seen at all
within that area.
• DEPRESSION : is an area of reduced sensitivity
without a surrounding area of normal
sensitivity
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7. • Generalized depression
(both peripheral and central contraction)
e g cataract
• Hemifield defect :
- Hemianopias
homonymous
heteronymous
• Altitudinal defect
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8. • Central scotoma
• Centrocaecal scotoma
• Arcuate scotomas
Seidel scotoma
paracentral scotoma
Bjerrum scotoma
• Nasal step
• Ring – double arcuate
• Barring of blind spot
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9. EXAMINATION TEST
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10. STATIC
• The location, size and duration of stimulus is kept constant and the
luminance is gradually increased until seen.
• Actual estimation of sensitivity of each point is THRESHOLD.
• SUPRA THRESHOLD stimulus used for screening.
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IMPORTANT :
one eye is tested at a time, other is occluded.
fixation of the patient has to be steady and is monitored throughout the test.
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11. KINETIC
• This presents a moving stimulus from a
non-seeing area to a seeing area.
• The most commonly used kinetic test is
Goldmann perimetry.
• It is repeated at various points around the
clock and a mark is made as soon as the
point is seen. These points are then joined
by a line (an isoptre).
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12. Standard automated
perimetry
HUMPHREY FIELD ANALYZER
• STATIC perimetry
• Measurement of threshold values
• Comparison to normative data
• Inbuilt program for analysis – diagnosis and progression
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13. ADVANTAGES
• Removal of examiner variability
• More sensitive to subtle field defects
• Retests abnormal points automatically
• Gives reliability parameters like
fixation monitoring
Gaze tracking
False positive
False negative
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14. PROGRAMS / PATTERNS
30-2 – gold standard
24-2
10-2
MACULAR
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15. MACULA PROGRAM :16
locations within the central 5°
with 2° spacing. Each location
is tested three times
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16. Requirements
• Selection of adequate test
• Proper environment
• Comfortable sitting position
• Adequate size of pupil >3mm
• Adequate Near correction
• Proper explanation –
• Reassurance – not all points will be seen
- test can be paused by keeping the response button
pressed
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17. 17

18. ZONE 1 : Patient data&Test data
Patient data
• Name, DOB, eye
• Vision, refraction,
• Pupil diameter
Test data
• Date and time
• Program and strategy
• Background
illumination
• Test size, color,
duration, interval
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19. ZONE 2 : RELIABILITY
• Fixation monitor
• Fixation target – central
• Test duration
• Reliability indices
Fixation losses <20 %
Gaze tracking
False positives < 33%
(trigger happy)
False negatives < 33 %
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20. • Fixation loses= gaze monitor
Steadiness of gaze during test
Presenting stimuli to the blind spot.
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21. • False positive
Stimulus with a sound.
If the sound alone is presented &the patient
still responds.
False negative
Stimulus brighter than thershold.
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22. ZONE 3 : GREY SCALE
• Based on actual threshold values at each
location
• General identification
• Patient information
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23. ZONE 4 :TOTAL DEVIATION PLOT
• Numerical plot – indicates by
how much decibels in each
point depressed compared to
mean value in normal
population of similar age
Generalized depression due to
media opacities, refractive
error, miosis affect appearance
of a pattern
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24. ZONE 5 : PATTERN DEVIATION PLOT
• calculated by adjustment for
generalized depression or elevation of
visual field
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25. ZONE 6 : GLOBAL INDICES
single numbers to denote whole field
• MEAN DEVIATION : average loss of sensitivity
from normal age matched population.
• PATTERN STANDARD DEVIATION :is a measure
of focal loss.
- Range over which change of sensitivity at all
the points has occurred, along with probability
-compensates for effect of generalized
depression or elevation of field on mean
deviation value
local defects affect PSD > MD
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26. ZONE 7 : GLAUCOMA HEMIFIELD
TEST
• Comparison of 5 corresponding of points in
superior hemifield with mirror images in inferior
hemifield
as glaucomatous change is:
Vertically asymetrical.
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27. OUTSIDE NORMAL LIMITS
all cluster pairs differ @ p < 1% OR
1 cluster pair differs @ p < 0.5%
BORDERLINE
hemifields differ @ p < 3%
GENERAL REDUCTION OF SENSITIVITY
overall field depressed @ p < 0.5%
ABNORMAL HIGH SENSITIVITY
overall field elevated( best 15 % points)
WITHIN NORMAL LIMITS
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28. ARTEFACTS
RIM ARTEFACTS
PTOSIS
MEDIA OPACITIES
• MIOSIS
• Refractive error
• High power plus and minus lenses
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29. high
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High false negative score

30. common causes of VF defect
Central field loss occurs with:
• Optic neuropathy
• Macular degeneration
• Macular hole
• Cone dystrophies
• A number of rare conditions like Best’s
disease, Stargardt's disease and
achromatopsia.
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31. Peripheral field loss occurs with:
• Retinitis pigmentosa
• Chorioretinitis
• Glaucoma
• Retinal detachment
• Leber's optic atrophy
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32. Focal field defects in optic
neuropathies
• Central scotoma
Demyelination
Toxic and nutritional
Leber hereditary optic neuropathy
Compression
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33. Focal field defects in optic
neuropathies
• Enlarged blind spot
Papilloedema
Congenital anomalies
• Respecting horizontal meridian
Anterior ischaemic optic neuropathy
Glaucoma
Disc drusin
• Upper temporal defects not respecting
vertical meridian
Tilted discs.
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34. Field defects in MS
• Diffuse depression of sensitivity.
• Altitudinal / arcuate defects.
• Focal centrocecal scotomas
• Focal defects with generalized depression.
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35. Visual field defects in psoriasis
• Central scotoma ,non specific paracentral
relative visual field defects
• probably induced by toxic posterior optic
neuropathy.
• The scotoma incompletely resolved after
cessation of Methotrexate (MTX) therapy.
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36. Visual field defects in diabetic
retinopathy
• Foveal thresholds were unaffected in the
diabetic patients but there is significant
reductions in visual field sensitivity.
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37. Nutritional optic neuropathy
• Field defects
Bilateral relatively symmetrical centrocaecal
scotomas
The margins of the defects are difficult to
define with a white target but easier using
red target.
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38. Lesions before the chiasm
• These will produce a field deficit in the ipsilateral
eye.
• Field defects from damage to the optic nerve
tend to be central, asymmetrical and unilateral.
• Lesions just before the chiasm can also produce a
small defect in the upper temporal field of the
other eye

39. 39

40. Lesions at the chiasm
Bitemporal hemianopia.
 If they spread up from below,
for example, pituitary tumours,
the defect is worse in the
upper field.
 If the tumour spreads down
from above , e.g.
craniopharyngioma, the lesion
is worse in the lower
quadrants.

41. Chiasmal tumor
• Visual loss may precede optic atrophy.
• Pupils usually react sluggishly to light.
• Afferent pupillary defect is usually present.
• Visual fields are abnormal.
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42. Pituitary adenomas a bitemporal
hemianopsia.
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43. Lesions after the chiasm
• These produce homonymous field defects.
• A lesion in the right optic tract produces left visual
field defect.
• Lesions in the main optic radiation cause
complete homonymous hemianopia without
macular sparing.
• Lesions in the temporal radiation cause congruous
upper quadrantic homonymous hemianopia
commonly with macular sparing.

44. 44

45. • Lesions in the parietal radiation (rare) cause
inferior quadrantic homonymous hemianopia
without macular sparing.
• Lesions in the anterior visual cortex (common)
produce a contralateral homonymous hemianopia
with macular sparing .
• Lesions in the macular cortex produce congruous
homonymous macular defect
• Lesions of the intermediate visual cortex produce
a homonymous arc scotoma, with sparing of both
macula and periphery.

46. right superior quadranopsia 46

47. 47

48. Occipital lobe lesions
• If both occipital lobes are injured then the patient
is in a state of cortical blindness.
• some patients deny their blindness and attempt
to behave as if they have vision.
• Markedly decreased vision and visual field in both
eyes (sometimes no light perception).
• With normal pupillary responses.
• Bilateral occipital lobe infarctions.

49. • Checkerboard Visual Field Defect: Bilateral
quadranopsia caused by two separate lesions
one above the calcarine fissure on one side of
the brain and one below on the opposite side
can produce a checkerboard pattern. This can
occur from two simultaneous events or events
separated in time.
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50. • A congruent visual field defect presents with
the same exact shape in the field of both eyes.
• Visual fields that are different in shape are
considered incongruent.
• More incongruent fields may point towards
lesion of the optic tracts
• while congruent defects point more towards
the visual cortex of the occipital lobe.
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51. Pupillary reflexes
• Pontine hge pinpoint pupil
• Midbrain lesiondilated fixed pupil.
• Dorsal tectal lesionslight -near dissociation.
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52. Light-near dissociation
• Compressive lesion as pinealoma
• involves the dorsal pupillomotor fibers
• Sparing ventral fibers concerning with near
reaction.
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53. Differential Diagnosis of “Light-
Near” Dissociation
• Bilateral optic neuropathy or severe retinopathy:
Reduced visual acuity with normal pupil size.
• Adie (tonic) pupil: Unilateral or bilateral irregularly
dilated pupil that constricts slowly and unevenly to
light. Normal vision. Adie (Tonic) Pupil.
• Dorsal midbrain (Parinaud) syndrome: Bilateral,
normal to large pupils. Accompanied by
convergence retraction nystagmus and supranuclear
upgaze palsy. Adie (Tonic) Pupil and “Convergence-retraction”
in Nystagmus.
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54. THANK YOU
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