glaucoma , field , VF

1. CHARACTERISTIC VISUAL
FIELD DEFECTS IN
GLAUCOMA
Dr ALSHYMAA MOUSTAFA
OPTHALMOLOGIST

2. CONTENTS
•Introduction
•What about the VF ?
•Anatomical distrubution of NF.
•Field Changes in glaucoma.

3. INTRODUCTION

4. • Glaucoma is the most common indication for
performing a visual field test.
• Glaucoma is defined as an optic neuropathy
characterized by progressive loss of retinal
ganglion cells and Nerve Fiber Layer (NFL)
with topographic changes of the optic nerve
head (neuroretinal changes) and associated
typical visual field loss.
• Several studies have suggested that the
retinal NFL defects precede the optic disc
changes and visual field loss.

5. WHAT ABOUT THE VF?

6. • “Island of vision surrounded by the sea of
darkness”
• There is a gradual rise in altitude of the
island from the periphery to the center
where it peaks, representing the increase in
sensitivity to light from the retinal
peripheryto the fovea.... Why....?!

9. What is ...
•Blind spot?
•Fixation point?
•Scotoma?
•Field defect?
•Bjerrum area?

10. Blind Spot
• Normally the optic disc correlates to the
physiological blind spot due to absence of
photoreceptors and is represented as a deep well in
the hill of vision.
• physiological blind spot is vertically oval;
approximately 7.5 × 5.5 degrees in extent and
represent the temporal visual field projection of
the optic nerve.
• Its usual location being 12° to 17° horizontal from
the fovea and 2°above and 5°below the horizontal
divide passing through the fixation

13. Fixation Point
• The maximum retinal senstivity, which is localized
in the center of the VF and Corresponding to fovea.
Temporal
Nasal

14. Scotoma
• It is an area of abnormal
retinal sensitivity surrounded
by areas of normal retinal
sensitivity.
• The scotoma is considered
absolute if the retinal
sensitivity is nearly absent and
relative when the sensitivity is
reduced as compared to the
normal.
• +Ve ,if the patient aware for it
and -ve,if not aware.

16. Field defect
• Absolute or relative decrease in retinal senstivity
extending to the peripheral field.

17. ANATOMICAL
DISTRUBUTION OF NF

22. FIELD CHANGES IN
GLAUCOMA

23. • Typically the first nerve fiber bundles
affected in glaucoma are those entering the
upper and the lower poles of the optic disc.
• When bundles of nerve fibers get damaged
at the optic disc, the region of visual field
supplied by these fibers looses its visual
sensitivity resulting in a localized depression
or scotoma.

24. Visual field defects
• Lesions affecting the papillomacular bundle produce a central
sscotoma.
• If this central scotoma is connected with the physiological blind spot it is
described as cecocentral scotoma.
• Damage to some of the fibers of the papillomacular bundle not
involving the fixation produces a paracentral scotoma.
• Damage to the temporal arcuate retinal nerve fibers givesrise to
characteristic arcuate scotomas, which finish abruptly at the horizontal
meridian in the nasalfield.
• Damage to the vascular supply of the inner retina, resulting from
vascular occlusion, will typically give rise to large scotomas,
corresponding to the retinal areasinvolved.
• Lesions affecting nasal retinal fibers produce temporal wedge defdect.

26. Field Changes in
glaucoma
NON SPECIFIC
• Generalized depression
• Baring of the blind spot
• Enlarged blind spot
SPEIFIC
• Early:
1. Paracentral scotoms
2. Seidel scotoma
3. Nasal step
• Late:
1. Arcuate scotoma
2. Ring scotoma
3. Ronne Nasal step
• Advanced:
1. Tunnel vision
2. Blind

34. GLAUCOMA OR NOT ?
Anderson criteria

35. ANDERSON CRITERIA
Minimum criteria to label a field defect as
glaucomatous as defined by Anderson are:
1. A cluster of 3 or more non edge points in a location
typical for glaucoma, that are depressed to an
extent < 5 percent of the population with one of
these points depressed to an extent found in < 1
percent of the population on consecutive fields.
2. The CPSD or the PSD depressed to a level found in
< 5 percent of the population on consecutive fields
3. Lastly the GHT outside normal limits on atleast 2
fields.

36. Note:
• In the presence of all these criteria the field can be
labeled glaucomatous, as it is highly suggestive of
glaucoma.
• Even in the presence of one positive criterion
clinical correlation should be made.

37. Schematic illustration of
different types of glaucoma
defect patterns
(a) Nasal step,
(b) Temporal wedge,
(c) Superior arcuate defect
(d) early superior paracentral
defect at 10°.
(e) Superior fixation-threatening
paracentral defect.
(f) Superior arcuate with peripheral
breakthrough and early inferior
defect.

39. GRADING OF GLAUCOMA
Hodapp classification

41. CASES

42. CASE 1
• Clinical history—> 61 years old male patient with
complains of decreased vision right eye.
• On examination the Right eye BCVA was 6/60 and
IOP was 26 mm Hg.
• There was significant cataract and shallow anterior
chamber and gonioscopy revealed closed angles in
the right eye.
• ONH showed -> 0.9:1 CD ratio with notching.

46. • Interpretation of fields—24-2 SITA standard of the
right eye showed advanced field loss impinging the
macula with a temporal island of vision.
• Note the dense nature of the defect with 0 dB
retinal sensitivities at most of the test locations.
• Total deviation plot shows generalized depression
due to cataract with superimposed glaucomatous
field defect and pattern deviation plot highlights
the advanced glaucomatous field defect.

47. • The 10-2 threshold test revealed similar defect.
• Macular test was also done to evaluate for macula.
• Note the macular threshold program printout has
only gray scale, threshold values and the depth of
the defect.

48. CASE 2
• Clinical history—> 88 year old male patient with
known primary open angle glaucoma well
controlled on antiglaucoma medication and
cataract in both eyes.
• BCVA 6/36 OU.
• IOP was 14 mm Hg on antiglaucoma medication in
both eyes.
• Optic nerve head in the Right eye showed 0.6:1
CDR with a large inferior rim notch. Left eye
showed 0.3:1 CDR with healthy NRR.

50. • Interpretation of fields—> 24-2 SITA standard test
showing RIGHT EYE dense superior arcuate
scotoma corresponding to the inferior rim notch.
• Note the foveal threshold of 23 dB corresponding
to a visual acuity of 6/36.
• Total deviation shows generalized depression due
to cataract
• which corresponds to a negative MD of –15.6 dB
with a significant p value.
• Pattern Deviation highlights the hidden scotoma in
the superior arcuate area corresponding to a
significant PSD of 10.94 dB.

51. CASE 3
•Clinical history—> 32 years old male
patient with juvenile open angle
glaucoma well controlled on topical
medication.
•ONH evaluation of the right eye
revealed 0.7:1 CD ratio with marked
superior rim thinning.

53. •Interpretation of fields—>
•Right eye 30-2 SITA standard test
showing classical inferior arcuate
scotoma corresponding to the ONH
findings.

54. CASE 4
•Clinical history—> 62 years old
female patient with POAG well
controlled on topical medication.
•ONH examination of Rt eye showed
0.65 CD ratio with marked inferior
rim thinning.

56. •Interpretation of fields—> Rt eye
24-2 SITA standard showing
superolior arcuatet scotoma with
nasal stept corresponding to the
ONH findings.

57. •Clinical history—60 years old male patient
with POAG well controlled
•on topical medication. ONH evaluation
showed 0.65:1 CD ratio with
•marked inferior rim thinning in right eye.
•
CASE 5

59. • Interpretation of fields—Right eye 24-2
SITA standard test showing
• Seidel’s scotoma in the superior hemifield
corresponding to the ONH
• findings.

60. THANKS