A detailed presentation covering all aspects of amblyopia, a form of cortical visual impairment, defined clinically as a unilateral or bilateral decrease of visual acuity (VA) that cannot be attributed to structural abnormalities of the eye or visual pathway

1. AMBLYOPIA & ITS MANAGEMENT
DR. ARVIND KUMAR MORYA
MBBS, MS OPHTHALMOLOGY(GOLD MEDALIST), MNAMS,
CATARACT(MICS), GLAUCOMA, PAEDIATRIC OPHTHALMOLOGY,
STRABISMUS,REFRACTIVE AND MEDICAL RETINA SERVICES,
ASSOCIATE PROFESSOR AND HEAD ,
DEPARTMENT OF OPHTHALMOLOGY,
AIIMS, JODHPUR

2. AMBLYOPIA
• DEFINITION
• EPIDEMIOLOGY
• PATHOPHYSIOLOGY
• CLASSIFICATION AND TYPES
• CLINICAL FEATURES AND DIAGNOSIS
• TREATMENT MODALITIES.

3. DEFINITION
• Amblyopia (lazy eye) is a form of cortical visual impairment, defined clinically
as a unilateral or bilateral decrease of visual acuity (VA) that cannot be
attributed to structural abnormalities of the eye or visual pathway.
• For clinical purpose difference of > 2 lines between two eyes
• Most common cause of decreased vision in childhood
• < 6/9 VA

4. Normal vision Amblyopia ( Loss of
vision)

5. PREVALENCE AND EPIDEMIOLOGY
• Prevalence in developed countries- 1-5 %
• In India affects 1-4 % of children (5-15 years)
• Prevalence varies in different parts of the world, with highest in
European countries
• Four times more frequent in premature children
• Six times more frequent in children with delayed MILESTONES

6. PATHOPHYSIOLOGY
 Amblyogenic factors
 Retinal factors
 Active cortical inhibition

7. AMBLYOGENIC FACTORS
VISUAL DEPRIVATION
Monocular
Seen in strabismic ,
anisometropic, stimulus
deprivation amblyopia
Binocular
Seen in bilateral cataract,
ametropia and bilateral
high refractive errors
LIGHT DEPRIVATION
Usually seen in children
with unilateral or bilateral
complete cataracts.
ABNORMAL
BINOCULAR
INTERACTION
-produces profound
amblyopia due to
competition amblyopia.
-seen in strabismic,
anisometropic and
unilateral stimulus
deprivation amblyopia.

8. VISUAL DEPRIVATION
Lack of Retinal Stimulation
Underdevelopment of corresponding
visual cortex

10. RETINA IN THE DEVELOPMENT OF AMBLYOPIA
• Decreased sensitivity of foveal cones in amblyopia
• The reduced input from rods and cones in the affected eye causes certain
neurophysiologic changes, transmitted to the CNS which triggers amblyopia.

11. ACTIVE CORTICAL INHIBITION
• A developmental defect of spatial visual processing occurring in the visual
pathway
• Poor transmission from the fovea, optic nerve to the striate cortex of the
affected eye.
• Lateral geniculate body & striate cortex develop abnormally.
• Ganglion cells in foveal area are affected; shrinkage of LGB nucleus &
striate cortical fibers in the amblyopic eye.
• Loss of binocularly driven cells in LGB & striate cortex.

12. CLASSIFICATION AND TYPES
Amblyopia Classified Mainly Into 2 Groups:-
AMBLYOPIA OF ARREST
• Occurs When Binocular Reflexes Are
Immature
• The suppression occurs quickly and
amblyopia of arrest develops
• Difficult to treat
AMBLYOPIA OF EXTINCTION
• Occurs when binocular reflexes are
mature
• Visual acuity has already developed
so chances of suppression and
amblyopia becomes less
• If treatment is started early, functions
can be recovered to great extent

13. Functional
amblyopia
Organic amblyopia
Reversible Irreversible
Refers to obligatory
psychical suppression of
the retinal image
Refers to partial loss of
vision caused by
undetectable organic
lesions in the eye or in the
visual pathway
Types: Strabismic,
Anisometropic, Ametropic,
Meridional, Stimulus,
Deprivation
Types: Nutritional, Toxic,
d/t retinal diseases,
Idiopathic
Usually seen in childhood Can cause visual acuity
defect at any age

14. TYPES OF AMBLYOPIA DEPENDING ON
THE CAUSE:-
1. STRABISMIC AMBLYOPIA
2. VISUAL DEPRIVATION AMBLYOPIA
3. ANISOMETROPIC AMBLYOPIA
4. AMETROPIC AMBLYOPIA
5. MERIDIONAL AMBLYOPIA
6. TOXIC AMBLYOPIA

15. STRABISMIC AMBLYOPIA
• Seen in patients with unilateral constant squint who
strongly favour one eye for fixation from birth to 6
years of age.
• Seen far more often in esotropes than the exotropes.
• Most common form of amblyopia.
• Strabismic amblyopia typically shows better grating
and pattern acuity compared to snellen’s acuity.
• Neutral density filter effect and eccentric fixation are
commonly observed.

16. Normal eye Deviating Eye
POOR AIM

17. CLASSIFICATION OF FIXATION:-
1. Central Fixation- Foveolar Fixation
2. Eccentric Viewing-
• Extrafoveal Point Because Of Central Suppression Scotoma.
• Fovea Still Not Lost Its Principle Visual Direction.
• Patient Look Past The Object They Have Been Asked To Fix.
3. Eccentric Fixation- Fovea Lost Its Principle Visual Direction.
• Parafoveolar -Just Outside The Foveal Reflex.
• Parafoveal - Outside But Close To Foveal Wall.
• Paramacular - On Or Just Outside The Rim Of The Macula.
• Peripheral- Outside The Macula, Anywhere B/W The Macula And Extreme Retinal
Periphery.

18. VISUAL DEPRIVATION AMBLYOPIA
• Amblyopia ex anopsia or disuse amblyopia.
• Caused by those conditions wherein one eye is
prevented from seeing early in life.
• Most common cause is congenital cataract or early
acquired cataract, but complete ptosis, corneal opacity
and vitreous hemorrhage may also implicated.
• Least common but most damaging and difficult to
treat.

19. IN CHILDREN:-
• Less than 6 years- severe amblyopia.
• After 6 years- less harmful.
• Occlusion amblyopia- type of deprivational amblyopia caused
by excessive therapeutic patching.

20. Normal eye Eye with Cataract
POOR CLARITY

21. ANISOMETROPIC AMBLYOPIA
• Refers to the amblyopia occurring in an eye having
higher degree of refractive error than the fellow eye.
• Known as suppression amblyopia, straight eye
amblyopia.
• 2nd most common amblyopia.
• Vision deprivation as well as the abnormal binocular
interaction that is caused by unequal foveal images in
the two eyes, might be playing role in the development
of amblyopia.

22. • Amblyopia is more common and is of higher degree in patients with
anisohypermetropia than in those with anisomyopia.
• Mild degree of hyperopic or astigmatism anisometropia (1-2 D)-
mild amblyopia
• Mild myopic anisometropia (less than -3 D)- NO AMBLYOPIA
• Unilateral high myopia (-6 D)- SEVERE AMBLYOPIA

23. Anisohypermetropia Anisomyopia

24. AMETROPIC AMBLYOPIA
• Bilateral amblyopia occurring in children with
bilateral, high, approximately equal, uncorrected
refractive error.
• Result from the effect of blurred retinal images alone.
• Commonly due to high hyperopia or astigmatism.
Hyperopia > +5D
Myopia > -10D
Astigmatism > 2.5D

25. MERIDIONAL AMBLYOPIA
• Amblyopia occurring in pts with uncorrected astigmatic
refractive error due to selective visual deprivation for visual
stimuli of a certain spatial orientation.
• Meridional amblyopia is a selective amblyopia for a specific
visual meridian.
• Occurs when a child progresses through the critical period
with one visual meridian in sharper focus than the other.
• 1.25 D of astigmatism may cause amblyopia.

26. TOXIC AMBLYOPIA
• It’s a nutritional optic neuropathy, where a toxic reaction in the
optic nerve results in visual loss.
• Various poisonous substance and nutritional factors may cause
the condition.
• Eg.-
Drugs- Chloramphenicol, Ethambutol
Tobacco- Pipe Smokers, Excessive Smokers
Alcohol
Chemicals- Lead, Methanol
Nutritional Disorders- Lack of Vit A and Zinc

27. CLINICAL CHARACTERISTICS
• Decreased visual acuity
• Decreased stereoacuity
• Fixation reflex
• Crowding phenomenon
• Effect of neutral density filter
• Contrast sensitivity
• Fixation pattern

28. WHAT ARE THE SIGNS AND SYMPTOMS OF AMBLYOPIA?
Symptoms Signs
• No symptoms • No obvious signs, unless
severe abnormality is present
• Blurred vision • Rubbing or squinting of
eyes
• Reduced vision • Misaligning eyes
• Reduced contrast sensitivity • Reduced VA and droopy
eyelid

29. CLINICAL EVALUATION & DIAGNOSIS
• Thorough clinical history
• Binocular red reflex test
• Binocularity/stereo acuity testig
• Evaluation of visual acuity and fixation pattern
• Binocular alignment and ocular motility
• External examination
• Pupillary examinaion
• Thorough ocular examination including fundus examination.
• Cycloplegic retinoscopy/Refraction
• Neutral density filter and testing for crowding phenomenon.

30. VISUALACUITY
• Two line difference between amblyopic and normal eye
• For bilateral amblyopia the VA should be less than 20/40 in each eye
• But in children there will be difficulty in assesing VA
Infants-fixation preference
Preverbal children- Preferential looking test, Optokinetic nystagmus test,
Visual evoked potential test
2-3 years- E-charts, Pictoral charts
>3 years- Snellen's charts, HOTV charts

32. PREFERENTIAL LOOKING TEST

33. STEREOACUITY
• Presence of amblyopia can be detected by defective
performance on various stereograms.
• Two pencil test is a clinically useful test and can be applied
even when VA recording is unreliable or not possible.
• Can also be measured by titmus fly test, random dot
stereogram.

34. Titmus fly test

35. Two-pencil Test:
A. Examiner holds pencil vertically in front of the
patients. The patient’s task is to touch the upper
tip of the examiner’s pencil with one swift
movement from above.
B. Patient passes the test with both eyes open.
C. Patient fails the test with one eye closed (or
when both eyes are open but stereopsis is
absent).

36. FIXATION REFLEX
• Useful tool to assess VA in children <5yrs of age
• Central steady and maintained (CSM) fixation implies good
Type of fixation VA
Affixation <3/60
Unsteady fixation 3/60 to 6/60
Central but not maintained 6/60 to 6/18
Central but strong preference for other eye 6/18 to 6/9
Alternate fixation 6/6

37. Alternating fixation- A, patient with right
esotropia. B, covering of OS requires patient to
fixate with OD; under the cover, OS turns inward.
C, on uncovering OS, OD maintains fixation and
OS stays turned inward. This fixation behavior
suggests equal visual acuity in either eye.
Fixation preference for OS- A, Patient with right
esotropia. B, Covering OS forces the patient to
fixate with OD, OS turns inward under cover. C,
Removal of cover results in immediate return of
fixation with OS and right esotropia. This fixation
behavior suggests reduced visual acuity OD,
especially when OD fixates unsteadily and
performs searching movements while the left eye
is covered.

38. Strong fixation preference in a strabismic infant- A, A child with right esotropia may not object to having
the deviated eye covered but protests occlusion of the dominant left eye. B, In this patient amblyopia of OD
must be suspected.

39. CROWDING PHENOMENON
• Amblyopia patients exhibit better VA for single optotypes than for letters placed
in a row
• Although not specific for amblyopia,it may be pronounced in amblyopic eye
compared to better eye
• Single line acuity improves more than line acuity during treatment
• So it is important to record both single letter and line visual acuity every time
as it is prognostic indicator

40. • Vision testing with single optotypes is likely to over estimate VA in pts with
amblyopia
• More accurate assesment of mono-ocular VA is obtained with the presentation
of line of optotypes or single optotype with crowding bars that surround
the optotype being identified

41. NEUTRAL DENSITY FILTER
• A neutral density filter reduces overall luminance without inducing a
color change.
• Decreased luminance of the visual target results in diminished
central acuity in normal eyes.
• Decreased illumination of visual targets has less of an effect on
amblyopic eyes because they are not using central acuity
• It was found that neutral filters profoundly reduce vision in eyes with
organic amblyopia whereas vision of eyes with functional amblyopia
was not reduced and occasionally even slightly improved.
• Hence it can be used to differentiate the two.

43. CONTRAST SENSITIVITY
• Reduction in contrast sensitivity more
for higher frequencies
• Improves during amblyopia therapy and
useful to monitor the progress
• Contrast threshold becomes normal in
strabismic amblyopia when luminance
levels were reduced, while the deficit
persists in anisometropic amblyopia PELLI ROBSON CONTRAST
SENSITIVITY CHART

44. FIXATION PATTERN
• Bangerter’s classification of fixation patterns in
amblyopia
I. Central fixation
II. Eccentric fixation (nonfoveolar)- common type
III. No fixation
• Patients with eccentric fixation appear to be looking to
the side,not directly at the fixation target. They have poor
smooth pursuits,so they do not accurately follow a
moving target.
• Can be tested in old coperative children by visuoscope

45. Eccentric fixation- A, Sound eye fixes with the fovea (left) and the amblyopic eye eccentrically fixates in an
area of fixation (right). B, Right eye is covered, and eccentric fixation persists with patient viewing in an
eccentric area.
Sound Eye Amblyopia Eye

46. OTHER FEATURES
• VEP Reduction in amplitude and slightly
prolonged latency
• Afferent pupillary defect may be seen
• Normalisation of VA in dim light occasionally
• Occasionally latent nystagmus

47. MANAGEMENT

48. Visual Cortex Plasticity
4y
Age
2y 6y
MOSTLY CURABLE
IF TREATED BEFORE SIX YEARSOLD.
8y

49. IMPORTANCE OF TREATMENT
• If left untreated, amblyopia produces a range of functional
deficits.
• Binocular function is also compromised
• The presence of amblyopia (or its treatment) impact on
educational attainment, future career opportunities, self-esteem
& quality of life

50. GOAL OF TREATMENT
• To restore and improve visual acuity by two strategies:-
I. Present clear retinal image to the amblyopic eye
o Eliminate causes of visual deprivation
o Correcting visually significant refractive errors
II.Make the child use the amblyopic eye
• Recommended treatment should be based on-
Patient’s age, VA, compliance with previous treatment &
physical, social and psychological status

51. TREATMENT MODALITIES
Treatment of amblyopia involves following steps:-
1) Eliminate any obstacles to vision, such as cataract.
2) Correct any significant error.
3) Force use of the poorer eye by limiting use of the better eye.

52. What would be the perfect amblyopia therapy?
 Effective
 Good compliance
 Acceptable to patients and parents
 Quick
 Safe
 Easy to administer
 Cost effective
 Well maintained

53. Choices of Treatment
The choices of treatment of amblyopia are used alone or in
combination to achieve goal of treatment
1. Passive Therapy
The patient experiences a change in visual stimulation without any
conscious effort
i. Proper refractive correction
ii. Occlusion
iii. Penalization

54. 2. Active Therapy
It is designed to improve visual performance by the patient’s conscious
involvement in a sequence of a specific, controlled visual task that
provide feedback
i. Pleoptics
ii. Near activities
iii
.
Active stimulation therapy using CAM vision stimulator
iv. Syntonic phototherapy
v. Role of perceptual learning
vi. Binocular stimulation
vii. Software-based active treatments
viii. Exposure to dark

55. Passive
Therapy
Refractive
Correction
OcclusionPenalization

56. Proper Refractive Correction
Purpose
• To provide sharp images and providing optimal environment for amblyopia
therapy
• Give patient proper optical correction alone
- Short period of time (6-8 weeks) before initiation of other therapy
- In case of refractive amblyopia, a progressive improvement in acuity
for up to 16 - 22 weeks has been shown in some pts after refractive
Correction.

57. When to Prescribe
• Table showing the recommended refractive error beyond which glasses should be prescribed in a
specific age group (American Academy of Ophthalmology)
Type of
refractive error
Age (0-1 year) Age (1-2 year) Age (2-3 year) PEDIG
Isometropia > -3.00 > -3.00
Myopia > -4.00 > -4.00 > +4.50 > +3.00
Hyperopia > +6.00 > +5.00 > +1.50
Hyperopia with
esotropia
> +2.00 > +2.00 > +2.00
Astigmatism > +3.00 > +2.50
Anisometropia
(without
strabismus)
> -2.00 > -1.00
Myopia > -2.50 > -2.50 > +1.50 > 1.00
Hyperopia > +2.50 > +2.00 > +2.00 > +1.50
Astigmatism > 2.50 > +2.00

58. Occlusion Therapy
• The most powerful and effective means of treating
amblyopia
• Highly effective until 8 years of age
• New studies have shown improvements upto 24 yrs of age
• Cover good eye to stimulate amblyopic eye
• Success rate 30-92%

59. • When fixation is central: simple & effective
• When fixation is eccentric: < 7 years central fixation recover
• Older the child harder to regain central fixation
Mode of Action
Prevent fixating eye taking part in act of vision and removes inhibitory
stimulus that arises from stimulation from fixating eye (non-amblyopic
eye)

60. TYPES OF OCCLUSION
Occlusion
Total or
Partial
Conventional
or Inverse
Full Time or
Part Time

61. Total VS Partial Occlusion
Total Partial
• All light is prevented from entering
eye
• Does not cut off the total light entering
eye
• Employed in amblyopic eyes
with acuity less than 6/24
• Degrades the vision of
normal eye such that
amblyopic eye gets better
vision and preference
• Occlusion using elastoplast,
gauze pad, tape, doynes
rubber occluder
• Occlusion using cellophane,
transparent nail polish, or a
higher plus lens

62. Conventional VS Inverse
Conventional Inverse
• Occlusion of sound eye • Occlusion of amblyopic eye so that
eccentric fixation becomes less fixed
Full Time VS Part Time
Full time Part time
• Removed only while going to bed at night • Short time each day during close work or
watching television
• Choice of initial Rx • In relapses after Rx and also for
maintenance

63. Patches Micropore tape with soft tissue paper
Spectacle patch Doyne’s occluder Opaque Contact LensFrost glass

64. How to go about Occlusion?
• Motivation of child and parents
• Active vision exercises by amblyopic while non amblyopic eye is
occluded
• Occlusion is continued till amblyopic eye has developed equal
vision and equal preference of fixation
• May take 3-6 months
• If there is no improvement, then treatment is stopped
• Maintenance treatment is continued at least up to 9yrs of age
with part time occlusion and exercises

65. Loss of depth feeling
Rash
Occlusion Amblyopia
DISADVANTAGES OF
OCCLUSION
Mental Pain
Low Adherence
4 [month] → 30%

66. Fig. Mean compliance with prescribed dose across all individuals still in treatment.
Days with fewer than 10 individuals remaining in treatment not shown.
VisualPsychophysicsandPhysiologicalOptics| September 2013ComplianceWith Occlusion Therapyfor
ChildhoodAmblyopia Michael P.Wallace;CatherineE.Stewart; Merrick J.Moseley; DavidA.Stephens;
Alistair R.Fielder
LOW ADHERENCE
4 [MONTH] → 30%

67. Prognostic considerations
• Younger the age better the prognosis
• Type of amblyopia: myopic anisometropia > hyperopic anisometropia >
strabismic amblyopia > stimulus deprivation
• Pre-treatment VA
• Pt. compliance and parent education
• Type of occlusion
• Presence of astigmatism
• Type of fixation
• Near exercises
• Previous treatment
• Refractive correction

68. Treatment of Anisometropic Amblyopia
Spectacle correction only
Continue until no further
improvement
VA improves
Spectacle correction plus
occlusion of sound eye
No improvement
Equalization of VA OU or
optimal VA of amblyopic eye
has been reached
Spectacle Contact lens

69. Treatment of Strabismic Amblyopia
Correct Significant refractive error
Can hold fixation in either
eye or equal in both eye
Occlusion of the sound eye Penalization
Total Partial
Age 0-5 y 5 y or old
0-2y = 3:1
3-4y = 4:1
4-5y = 5:1
Frequent checks of
fixation preference
Occlude sound eye for
4-6weeks but not longer
before checking VA
in each eye
No Improvement
Alternating Penalization
Stop treatment after 3
months or treatment in
compliant patient

70. Penalization
 Therapeutic technique performed by optically defocusing the eye with better
vision by using cycloplegia or altering the eye glass lens
Indications
• No compliance for occlusion
• Mild degrees of amblyopia
• Maintenance after occlusion
• Anisometropic amblyopia

71. POWERFUL EYEDROPS FOR
DEFOCUSING

72.  Advantages: Cheap, better compliance
 Disadvantages: - Side effects of drugs
- Risk of occlusion amblyopia
- Systemic absorption
 Unless penalisation decreases the VA of dominant eye below the
amblyopic eye this form of treatment is not advised

73. Implications of the PEDIG
(Pediatric eye disease investigator group ) studies
• Children < 7 yrs and VA between 6/12 to 6/24
- 2 hrs and 6 hrs patching - same effect
• Children < 7 yrs and VA 6/30 - 6/120
- 6 hrs and full time patching - same effect
• Children < 7 yrs and VA 6/12 - 6/30
- Daily atropine produces similar effect as 6 hrs patching

74. • Children 7 to 18 yrs and VA 6/12 to 6/120
- 2 - 6 hrs patching leads to at least 2 line improvement
(if no previous treatment) but
- the compliance rate is poor in age >13 yrs
• Children < 8 yrs and VA 6/12 - 6/120
- Patching 2 hrs is better than spectacles alone

75. ACTIVE THERAPY

76. • Used for active stimulation of the fovea to overcome eccentric fixation and
improves the visual acuity
- The peripheral retina is dazzled with an intense light protecting
foveal area.
- After the light source is turned off, the fovea functions better as the
surrounding retinal area is in a state of hypofunction
- This can be followed by direct stimulation of fovea by pleoptophore
(bangerter’s method) or indirectly by producing after image (Cupper’s
method)
Pleoptics

77. PLEOTOPHORE EUTHYSCOPE

78. Disadvantages
• The technique is complex and requires an absolute co-operation of the
pt. and intelligence to appreciate after-images
• Daily sitting for a longer period of time is required
• Since occlusion of the dominant eye is a very successful simple and
inexpensive method of treating eccentric fixation, so the use of pleoptics
methods is abandoned
• Only indication is co-operative and intelligent child older than
6yrs having eccentric fixation

79. Treatment using grating stimuli

80. Method
• Non amblyopic eye is occluded
• Amblyopic eye is stimulated for 7 mins by slowly rotating
(at about 1 revolution per min) high contrast square wave
grating of different spatial frequencies
• The treatment is carried out once in a week for 3 to 4 weeks
• Advantages over the conventional occlusion therapy
• The sound eye remains open between the weekly treatment
sessions
CAM visual stimulator

81. Principle
• Assumption that rotating grating provides specific stimulation
for cortical neurons
Present status of CAM vision stimulator
• This technique is not as effective as conventional occlusion therapy
• So it has failed to replace time tested conventional occlusion therapy for
the treatment of amblyopia
• Some workers use this technique as supplementary to occlusion
therapy in co-operative pts. with supportive who can carry out the
treatment at home

82. • Recently a new treatment has been described based on a similar principle,
namely, the use of grating stimuli to activate certain cortical cells.
• The treatment is computer-based and is intended to supplement occlusion
treatment, particularly in patients beyond childhood.
• The treatment comprises a computer game viewed on a monitor against
the background of a low spatial frequency drifting sine wave grating
REVITAL VISION

83. • Based on the idea that stimulation of motion-sensitive cells
might help to improve function of form-sensitive cells by
synchronisation of responses
• Efficacy of treatment is higher for the computer based
method combined with occlusion than for occlusion only

84. • Mallet IPS unit
• described as the "heightened
response" to a visual stimulus
• The targets
– consisted of slides containing much
detail of varying type and angular
dimension
– viewed against a red flickering
background.
•
•
Red slight stimulation at 4Hz
detailed visual task for 20-30
minutes
INTERMITTENT PHOTIC STIMULATION

85. 1. 2.
3. 4.

86. Role of perceptual learning in
amblyopia treatment

87. • PL employs repeatedly practicing a visual discrimination task,
eg: positional acuity, contrast sensitivity, stereo-acuity, etc.
• Recommended period for PL: 2hrs/ day, 5 days/ week, for a
period of 9 months
• Significant improvements found in VA and CS (Chen P. et al
2008, Huang C. et al 2006)
• Role of PL is still controversial, but utility is reported in adult
amblyope

88. Video Game Play & Brain Plasticity
• The intense sensory-motor interactions are immersed video-game play
• This might push brain functions to the limit
• Enables the amblyopic visual system to learn, on the fly, to
recalibrate and adjust, providing the basis for functional plasticity
• Game playing requires the allocation of spatial detection, and
localization of low contrast, fast moving targets, and aiming

89. • During occlusion therapy, the non-amblyopic eye is occluded i.e.
binocular vision is not encouraged during these periods
• It has been recognized that binocular stimulation may be important in the
treatment of amblyopia
• Offers support for binocular stimulation when treating amblyopia

90. • High-contrast red elements (miners and fireball) are seen by the amblyopic eye
• Low-contrast blue elements (gold and cart) are seen by the fellow eye
•
•
Gray elements (rocks and ground) are seen by both eyes
Both eyes must see the game for successful play
Fig: Dig Rush Game
Binocular iPad Game

91. Fig: Best-Corrected Visual Acuity (BCVA) at Baseline, the 2-Week Visit, and the 4-
Week Visit
 Binocular iPad game is a successful treatment for childhood
amblyopia and is more effective than patching at the 2-week visit

92. OCCLU-TAB: BINOCULAR GAMING TAB
• BOTH EYES ARE ALWAYS OPEN
• SAFER AND MORE EFFECTIVE
• EASIER FOR PATIENTS TO USE
Forparents
Forright-eye treatment
Forleft-eyetreatmentTouchblock
Forinfants
Polarizing Filter
For the Impaired Eye

93. *
IMPROVEMENT OFBCVA AT 2MONTHS AFTER
TREATMENT: EYE PATCH VS OCCLU-TAB
Treatment time: 3 days/a week, 60 minutes/day, 2months
0.4
0.2
0
0.6
0.8
1
Eye patch
ImprovementofBCVA(LogMAR)
*
Occlu-tab
* : Mann-whitney-U test, p=0.016

94. Occlu-tab®
Vision Training Vision Training

95. Monocular fixation in a binocular field (MFBF) technique
• Principle: Training the amblyopic visual system to integrate information
from both eyes
• This technique involves the presentation of peripheral stimuli to both eyes,
while only the amblyopic eye is stimulated at the fovea

96. • Applied in a range of paper-based formats.
E.g, pt. may be instructed to complete tasks such as Crossword puzzles or
placing dots in the ‘o’ letters in a text, using a pen and wearing red-green
glasses, with the red lens in of the non-amblyopic eye
Monocular fixation in a binocular field (MFBF) technique

97. Interactive Binocular Treatment for Amblyopia
Concept
• Present separate images to each eye
• Dynamic visual scene
• Preferentially stimulating amblyopic eye
Patient motivation
• Interactive games and videos
• Encourage patient compliance
Shutter Glasses Technology
• Shutter glasses
• High definition screens
• Faster processing speeds

98. • PL is an area with clear potential for treating amblyopia
• Significant improvements in vision can result from training periods that
are relatively short using tasks that are relatively engaging, compared to
conventional occlusion
• It is important to be aware that the way in which these improvements arise is
not yet fully understood
• Further research is needed before optimal training strategies can be devised
and before the way in which those strategies modify visual function can
be fully understood

99. • Levodopa & citicoline are the most extensively studied drugs
• Plasticity of visual system during the sensitive period is dependent on
input from non-adrenergic neurons and thus can be subjected to
pharmacological manipulation
• Precursor for the catecholamine dopamine, a neurotransmitter, known to
influence visual system at retina and cortical level
• It either extends or reactivates the visual system’s sensitive period of
neural plasticity
• Catecholamine based medical treatment has been demonstrated to improve
vision in amblyopic eyes.
Pharmacological Therapy

100. ADVANTAGES
 Augments conventional occlusion
 Speeds up recovery of visual functions
 Improves compliance
 Possibility for adult amblyopes
 Reduces cost and duration of treatment

101. ACKNOWLEDGEMENTS
• DR. KAVITA BHATNAGAR, PROFESSOR AND HOD, DEPARTMENT OF
OPHTHALMOLOGY,AIIMS JODHPUR
• DR. MONIKA SAMOTA, SENIOR RESIDENT, DEPARTMENT OF
OPHTHALMOLOGY,AIIMS JODHPUR
• DR. ANUSHREE NAIDU, POST GRADUATE RESIDENT 3RD YEAR,
DEPARTMENT OF OPHTHALMOLOGY,AIIMS JODHPUR
• DR. SULABH SAHU, POST GRADUATE RESIDENT 2ND YEAR, DEPARTMENT
OF OPHTHALMOLOGY,AIIMS JODHPUR

102. Amblyopia is still an unsolved problem, the best
modality of treatment is still to be explored in
future
Thankyou