Evidence Based Treatment of Amblyopia in 2005

1
Evidence Based Treatment of Amblyopia in 2005

• What we have learnt from the Pediatric Eye
  Disease Investigator Group PEDIG
• Lionel Kowal

2
Rationale for PEDIG Amblyopia Studies

• Amblyopia is the most common cause of monocular
  visual impairment in children.
• Existing data on the treatment of amblyopia
  largely retrospective / uncontrolled.

3
PEDIG Network of community university- based
ophthalmologists and optometrists

• A Randomized Trial of Atropine Versus Patching
  for Treatment of Moderate Amblyopia in Children -
  ATS 1
• A Randomized Trial Comparing Part-time Versus
  Full-time Patching for Severe Amblyopia - ATS 2A
• A Randomized Trial Comparing Part-time Versus
  Minimal-time Patching for Moderate Amblyopia -
  ATS 2B
• Prospective Study of Recidivism After Cessation
  of Amblyopia Treatment - ATS 2C
• An Evaluation of Treatment of Amblyopia in
  Children 7-lt18 Years Old ATS3
• A Randomized Trial of Atropine Regimens for
  Treatment of Moderate Amblyopia in Children ATS4

4
Amblyopia Treatment StudyATS 1

• A Randomized Trial of Atropine Versus Patching
• for Treatment of Moderate Amblyopia in Children

The Pediatric Eye Disease Investigator Group. A
randomized trial of atropine vs patching for
treatment of moderate pamblyopia Archives of
Ophthalmology 2002120268-278
5
Objectives

• To compare patching and atropine as treatments
  for moderate amblyopia in children 3 to lt7 years
  old
• To develop estimates of the success rates of
  treatment
• To identify factors that may be associated with
  successful treatment

6
Study Design

• A randomized, controlled single-masked
  multi-center clinical trial
• 2 treatment groups
• Primary outcome VA _at_ 6 mo
• Treatment after 6 mo investigator discretion
  

Patching
Atropine
7
Eligibility

• Able to measure VA with single surrounded HOTV
• Strabismic and/or anisometropic amblyopia
• Visual Acuity
• Amblyopic eye 6/12 to 6/30
• Sound eye 6/12 or better
• 3 lines or more interocular difference
• lt 2 mo of amblyopia therapy in prior 2 y

8
Holmes, JM, Beck, RW, et al The Amblyopia
Treatment Study Visual Acuity Testing Protocol
Archives of Ophthalmology 20011191345-1353.
9
Patching Treatment

• Initial
• 6 h/d up to all waking hours at investigators
  discretion
• Subsequent (_at_ 17 w)
• If lt6/9 and lt3 line improvement, increase up to
  all or all but one waking hours
• If gt6/9 or gt3 line improvement, investigator
  could decrease patching to a minimum of 1 h/d

10
Atropine Treatment

• Initial
• 1 drop atropine 1 daily in sound eye
• Subsequent (_at_ 17 w)
• If lt6/9 and lt3 line improvement, replace
  hypermetropic lens of sound eye with plano
• If gt6/9 or gt3 line improvement, investigator
  could decrease atropine to 2/w

11
Amblyopia Treatment Index

• Questionnaire of 18 items, each scored from 1 to
  5, with 5 representing the most difficult
• Three subscales measured
• adverse effects of treatment
• difficulties with compliance
• social stigma of treatment
• Items are summed to create each subscale score,
  then scaled to a common range

The Pediatric Eye Disease Investigator
Group Impact of Patching and Atropine Treatment
on the Child and Family in the Amblyopia
Treatment Study Archives of Ophthalmology
20031211625-1632
12
Patient Characteristics
N419
Female 47 Caucasian 83 African
American 5 Hispanic 6 Asian 2 Mixed 2
Other 2
13
Age n419
lt3 y 2 3 to lt4 y 15 4 to lt5 y 20 5 to
lt6 y 33 6 to lt7 y 30 Mean Age 5.3 y
14
Cause of Amblyopia n419
Strabismus 38 Anisometropia 37 Combined-mecha
nism 24
Prior Treatment
26 received previous treatment for amblyopia
15
Patient Follow Up
Patients Randomized 419
Patching Group 215
Atropine Group 204
6 Month Exam Completed 208 (97)
6 Month Exam Completed 194 (95)
2 Year Exam Completed 176 (86)
2 Year Exam Completed 187 (87)
16
Patching Group Number of Hours of Patching
Prescribed
At Enrollment
Maximum
gt12 hours
gt12 hours
6 hours
6-7 hours
10 hours
8 hours
8-9 hours
10-11 hours
The number of hours prescribed at baseline was
the maximum for 80 of patients
17
Atropine Group

• All patients prescribed one drop of 1 atropine
  daily
• A plano spectacle lens was prescribed for the
  sound eye during follow up for 56 /194 patients

18
Amblyopic Eye Acuity at 6 Months
Patching Atropine (N208)
(N194) Mean improvement from 3.16 lines
2.84 lines baseline Mean acuity at 6 months
6/9 6/9-2 (Snellen approximation) gt6/9 or
gt3 line improvement from baseline 79
74
19
Amblyopic Eye at 6 Months
N208
Amblyopic Eye Visual Acuity Cumulative
Distribution
N194
gt20/16
gt20/20
gt20/25
gt20/32
gt20/40
gt20/50
gt20/63
gt20/80
gt20/100
gt20/125
gt20/160
6-month Amblyopic Eye Visual Acuity
20
Amblyopic Eye Mean Acuity at Each Visit
20/20
20/25
20/30-
20/30
20/30
20/40
20/40
20/30-2
20/40
20/50
20/50
20/60
20/60-
20/80
21
Treatment Effect in Subgroups at 6 Months

• Effect of treatment was similar in subgroups
  based on
• Age
• lt5 years old, gt5 years old
• Cause of amblyopia
• strabismus, anisometropia, combined
• Baseline visual acuity in amblyopic eye
• 20/80 to 20/100 , 20/40 to 20/60

22
Effect of Treatment on Sound Eye at 6 Months

• A decrease in visual acuity of 1 or more lines at
  6 months
• patching - 17 patients (8)
• atropine - 47 patients (23)
• Some cases were due to improper refractive
  correction
• In other cases there likely was residual
  cycloplegia from atropine not having been
  discontinued

23
Atropine Side Effects
N208
Ocular Side Effects Any ocular side
effect 26 Types of ocular side
effects Lid/conjunctival irritation
4 Light sensitivity 18 Eye
pain/headache 2 Other 2 Facial
Flushing 2 Systemic Side Effects
3
Reported at any visit in first 6 months
24
Patching Side Effects
N215
Skin Irritation Mild 41 Moderate/Seve
re 6 Reported at any visit in first 6
months
25
Amblyopia Treatment Index

• Both treatments were well tolerated
• All 3 subscale scores were consistently worse in
  the patching group
• Median Score
• Subscale Patching Atropine
• Adverse Effects 2.25 2.00
• Difficulty with Compliance 2.20 1.80
• Social Stigma 3.00 2.00

26
Amblyopic Eye Acuity at 2 Years
Patching Atropine (N188)
(N179) Mean improvement from 3.7 lines
3.6 lines baseline Mean acuity at 2 years
20/322 20/321 (Snellen approximation) gt20/3
2 or gt3 line improvement from baseline
86 84
Two-year follow-up of a 6-month randomized trial
of atropine vs patching for treatment of
moderate amblyopia in children.Arch Ophthalmol.
2005 Feb123(2)149-57.
27
Amblyopic Eye at 2 Years
N188
Amblyopic Eye Visual Acuity Cumulative
Distribution
N176
gt20/16
gt20/20
gt20/25
gt20/32
gt20/40
gt20/50
gt20/63
gt20/80
gt20/100
gt20/125
gt20/160
6-month Amblyopic Eye Visual Acuity
28
Summary

• There was substantial improvement in amblyopic
  eye visual acuity with both treatments
• Improvement was more rapid in the patching group
• The difference between groups in amblyopic eye
  acuity at six months was small (about a third of
  a line)
• There was no difference between groups in
  amblyopic eye acuity after 2 years

29
Amblyopia Treatment StudyATS 2A, 2B, 2C

• AN EVALUATION OF PATCHING REGIMENS

30
Rationale

• Patching is most commonly prescribed. However,
  controversy exists concerning how much treatment
  is necessary.
• Most data on the response according to the daily
  dosage of patching are retrospective and
  uncontrolled.
• There is no standard of care once initial
  treatment of amblyopia is completed.

31
Randomized Trials

• Patching 2 hours versus 6 hours daily for
  moderate amblyopia (20/40 to 20/80)
• Patching 6 hours versus full-time for severe
  amblyopia (20/100 to 20/400)

32
Eligibility

• Age lt 7 years
• Able to measure visual acuity with single
  surrounded HOTV optotypes
• Strabismic and/or anisometropic amblyopia
• Visual acuity
• Amblyopic eye 20/40 to 20/400
• Sound eye 20/40 or better
• 3 lines or more interocular difference
• No more than 2 months of amblyopia therapy in
  prior 2 years

33
Study Design
Severe Amblyopia Trial 20/100-20/400
Moderate Amblyopia Trial 20/40-20/80
Randomize
Randomize
Full-time patching all or all but 1 hr per day
Part-time patching 6 hrs per day
Part-time patching 6 hrs per day
Minimal-time patching 2 hrs per day
Visit A 5 1 week Visual acuity testing both
eyes Ocular alignment assessment Amblyopia
Treatment Index
Visit B 17 1 week Visual acuity testing
(masked) both eyes Ocular alignment
assessment Stereoacuity Testing
34
Treatment Protocol

• Severe amblyopia 6 hours of patching
• Full time patching
• Moderate amblyopia 2 hours of patching
• 6 hours of patching
• All treatment groups were prescribed at least 1
  hour of near
• activities while patching.
• Investigator - Patching decreased to no less than
  7 hours per week
• Investigator - Patching could be continued,
  reduced, or stopped

35
Results ATS 2B 2 vs. 6 hours of patching for
moderate amblyopia (20/40 20/80)
The Pediatric Eye Disease Investigator Group A
Randomized Trial of Patching Regimens for
Treatment of Moderate Amblyopia in
Children Archives Of Ophthalmology
1212003603-611
36
Patient Characteristics
N189
Female 44
Caucasian 85
Age (mean) 5.2 years
Cause of Amblyopia
Strabismus 40
Anisometropia 33
Combined 27
Prior Amblyopia Treatment 14
37
Patient Follow Up
38
Amblyopic Eye Acuity at 4 Months
2 Hours Patching N92 6 Hours Patching N89
Mean improvement from baseline 2.4 lines 2.4 lines
Mean acuity at 4 months (Snellen approximation) 20/32-2 20/32-2
gt20/32 or gt3 line improvement from baseline 62 62
39
Amblyopic Eye Mean Acuity at Each Visit
40
Amblyopia Treatment Index

• Both treatments were well tolerated.
• The subscale scores were similar between the
  groups on the adverse event and treatment
  compliance subscales.
• On the social stigma subscale, which includes
  questions related to the patch making the child
  feel different, the 6-hour group was worse.
• Median Score
• Subscale 2 Hours 6 Hours
• Adverse Effects 2.13 2.13
• Difficulty with Compliance 2.33 2.33
• Social Stigma 2.67 3.00

41
Summary 2 vs. 6 hours for moderate amblyopia

• Amblyopia improved with both patching regimens,
  when combined with prescribing 1 hour of near
  activities
• There was no demonstrable advantage to the
  greater number of hours either in the rapidity or
  magnitude of improvement after 4 months of
  treatment

42
Summary - Adverse Effects

• We found no indication that 6 hours of patching
  compared with 2 hours of patching was associated
  with a higher rate of adverse effects on the
  sound eye acuity
• New heterotropias were rare

43
Conclusions

• When combined with prescribing 1 hour of near
  activities, 2 hours of daily patching appears to
  be as effective as 6 hours of daily patching in
  treating moderate amblyopia in children 3 to lt 7
  years of age
• A shorter duration of patching may ease the
  implementation of patching therapy and monitoring
  compliance for some parents

44
Results ATS 2A 6 hours vs. full time patching
for severe amblyopia (20/100 20/400)
The Pediatric Eye Disease Investigator Group A
Randomized Trial of Prescribed Patching Regimens
for Treatment of Severe Amblyopia in Children
Ophthalmology 2003112075-2087
45
Patient Characteristics
N 175
Female 46
Caucasian 83
Age (mean) 4.8 years
Cause of Amblyopia
Strabismus 27
Anisometropia 34
Combined 38
Prior Amblyopia Treatment 14
46
Patient Follow Up
47
Amblyopic Eye Acuity at 4 Months
6 Hours Patching N73 Full-time Patching N84
Mean improvement from baseline 4.8 lines 4.7 lines
Mean acuity at 4 months (Snellen approximation) 20/50 20/50-2
48
Amblyopic Eye Mean Acuity at Each Visit
Baseline Exam
Five-week Exam
Four-month Exam
20/040
20/050
20/50
20/50-2
20/063
20/63-2
20/63-2
20/080
20/100
Mean Visual Acuity Score
20/125
20/160
20/1601
20/160
20/200
20/250
Full-time N90
Six-hrs N85
Full-time N77
Six-hrs N75
Full-time N84
Six- hrs N73
49
Treatment Effect in Subgroups at 4 Months

• Effect of treatment was similar in subgroups
  based on
• Age
• lt5 years old, gt5 years old
• Cause of amblyopia
• strabismus, anisometropia, combined
• Baseline visual acuity in amblyopic eye
• 20/100 to 20/160 , 20/200 to 20/400

50
Amblyopia Treatment Index

• Both treatments were well tolerated
• The subscale scores were similar between the
  groups on the adverse event, treatment
  compliance, and social stigma subscale subscales
• Median Score
• Subscale 6 Hours Full-Time
• Adverse Effects 2.25 2.50
• Difficulty with Compliance 2.33 2.42
• Social Stigma 3.00 3.00

51
Summary 6 hrs vs. full-time for severe amblyopia

• Amblyopia improved with both prescribed patching
  regimens, when combined with prescribing 1 hour
  of near activities
• Compared to 6-hour patching, there was no
  demonstrable advantage to full-time patching in
  the rapidity or the magnitude of improvement
  after 4 months of treatment

52
Amblyopia Recurrence ATS 2C

• Prospective observational study
• 156 children with successfully treated amblyopia
  ready to stop treatment
• Treatment STOPPED at enrollment

Risk of amblyopia recurrence after cessation of
treatment.J AAPOS. 2004 Oct8(5)420-8.
53
Study Design
Enrollment 156 children
Study period off treatment
5w 13w 26w 52w
Previous Rx
Treatment STOPPED
54
Recurrence overall during 1-year follow-up
Recurrence ( 2 logMAR - Confirmed by repeat
testing) 21 (95 CI 14 to 28)
21
Alternative Definition Non replicated 2
logMAR VA
3
No recurrence
All recurrences - 24 (95 CI 17 to 32)
55
Timing of the 35 recurrences
14 (40)
Pts
10 (29)
5 (14)
6 (17)
Weeks
56
Patching vs Atropine
Patching Stopped (77 pts)
Atropine Stopped (23 pts)
21 Recurrence (95 CI 7 to 35)
25 Recurrence (95 CI 17 to 34)
57
Patching hours stopped
Recurrence 15 18 43
43
Patching hours stopped at enrollment
P0.008
58
Conclusions of Amblyopia Recurrence Study

• ¼ of successfully amblyopic children experience
  a recurrence over 1 year of f/u
• Recurrence risk is similar for stopping patching
  and atropine
• Most recurrences occur within 3 months early
  follow-up is critical but long term follow-up
  is also important
• If 6 or more hours of patching stopped
  recurrence risk is lower if patching is reduced
  to 2 hours per day before cessation suggests
  weaning is beneficial

59
An Evaluation of Treatment of Amblyopia in
Children 7-lt18 Years Old ATS3 Supported by
the National Eye Institute
60
PEDIG Pilot Study
A prospective, pilot study of treatment of
amblyopia in children 10 to lt18 years old.Am J
Ophthalmol. 2004137581-583.

• Eligibility
• Age 10 to lt18 years
• Amblyopic eye acuity of 20/40 to 20/160
• Treatment
• gt2 hours daily patching
• At least one hour of near activities during
  patching
• Outcome Visual acuity after two months of
  treatment
• Results Visual acuity improved gt2 lines in 18
  (27)
• of 66 patients

61
Objectives

• To determine the response rate to amblyopia
  treatment in children from 7 to lt18 years
• To determine the frequency of recidivism of
  successfully-treated amblyopia in children 7 to
  lt18 years

62
Eligibility

• Age 7 years to lt18 years
• Amblyopia associated with strabismus,
  anisometropia, or both
• Best corrected visual acuity in the amblyopic eye
  20/40 to 20/400
• Best corrected visual acuity in the sound eye
  20/25 or better
• No myopia in amblyopic eye gt-6.00 D spherical
  equivalent
• No amblyopia treatment (other than spectacles) in
  the past month and no more than one month of
  amblyopia treatment in the last 6 months

63
Study Design

• Randomized, controlled multi-center clinical
  trial
• Sample size gt360 children (gt90 in each of 4 age
  groups)
• Treatment groups
• Control Group Optical correction only
• Active Group Optical correction
• Patching plus near activities
• Atropine (patients lt13
  yrs only)
• Primary analysis Comparison of proportion of
  treatment
• responders
  between treatment groups

64
Study Flow
Enrollment Prescription of spectacles
Randomization (within 30 days of
enrollment) Visual acuity testing in new
spectacles
Randomized Trial Follow Up
Responders
Nonresponders
End of Study
Post-randomized Trial Follow Up
Active Group
Control Group
Observation Phase Follow Up Treatment is
discontinued
65
Enrollment/Randomization

• Screening/Enrollment Visit
• Patients are prescribed new spectacles (if
  needed)
• Randomization Visit (within 1 month)
• New spectacles are placed on patient for the
  first time
• Visual acuity is tested using E-ETDRS protocol,
  which yields a letter score
• Patient is randomized as long as visual acuity
  still meets eligibility criteria

66
Treatment Groups

• Patients are randomized to one of the following
  treatment
• groups
• Control Group
• Optical correction only
• Active Treatment Group
• Optical correction
• Patching 2-6 hours daily
• At least 1 hour of near activities daily during
  patching
• Atropine 1 one drop daily (pts lt13 yrs only)

67
Randomized Trial Follow Up

• Follow-up visits occur every 6 weeks up to 24
  weeks
• Visual acuity is tested with the E-ETDRS protocol
• Using the best of two measured amblyopic eye
  visual acuities, the patient is classified as a
  responder, nonresponder or neither
• When the patient meets criteria for either
  responder or non-responder and this is confirmed
  by masked exam, the randomized trial is over

68
Responder/Nonresponder Criteria

• Responder Criteria 10 letter (2 line) or more
  improvement in amblyopic eye acuity compared with
  acuity at randomization
• Nonresponder Criteria minimal improvement that
  is visit specific, but less than 10 letters by 24
  weeks

69
Post-Randomized Trial

• Nonresponders
• End study follow up
• Control group patients may start on active
  treatment outside study
• Responders
• Continue assigned treatment until no further
  improvement
• Once improvement has stopped
• Control Group patients end study, but may start
  on active treatment outside study
• Active Treatment Group patients discontinue
  treatment and enter the Observation Phase

70
Observation Phase

• Visits occur at 13 wks, 26 weeks, and 52 weeks
  after treatment discontinuation
• Visual acuity is assessed at each visit
• Recurrence acuity 10 or more letters worse than
  acuity at treatment discontinuation

71
RESULTS

• 507 patients
• 49 sites
• 1 to 33 patients/per site

72
Patient Characteristics 7 lt 13 YRS
N404 ()
TREATMENT (N 201) OPTICAL CORRECTION (N 203)
AGE 9.8 (1.6) 9.5 (1.7)
FEMALE 89 (44) 87 (43)
NO PRIOR TREATMENT 96 (48) 99 (49)
CAUSE OF AMBLYOPIA
Strabismus 52 (26) 52 (26)
Anisometropia 75 (38) 81 (41)
Combined 73 (37) 66 (33)
ACUITY IN AMBLYOPIC EYE
20/200 - 400 16 (8) 18 (9)
20/100 160 44 (22) 48 (24)
20/40 80 141 (70) 137 (67)
73
Patient Characteristics 13 lt 18 YRS
N103 ()
TREATMENT (N 55) OPTICAL CORRECTION (N 48)
AGE 14.7 (1.4) 14.9 (1.2)
FEMALE 31 (56) 25 (52)
NO PRIOR TREATMENT 36 (65) 33 (69)
CAUSE OF AMBLYOPIA
Strabismus 11 (20) 14 (29)
Anisometropia 20 (36) 17 (35)
Combined 24 (44) 17 (35)
ACUITY IN AMBLYOPIC EYE
20/200 - 400 2 (4) 3 (6)
20/100 160 20 (36) 16 (33)
20/40 80 33 (60) 29 (60)
74
Responder Rate 7 lt 13 YRS
TREATMENT (N 201) OPTICAL CORRECTION (N 203)
TOTAL 106 (53) 50 (25)
AMBLYOPIA LEVEL
20/40 80 (N 141/137) 70 (50) 30 (22)
20/100-400 (N 60/66) 36 (60) 20 (30)

PRIOR AMBLYOPIA TREATMENT
Yes (N 105/104) 42 (40) 14 (13)
No (N 96/99) 64 (67) 36 (36)
N ()
All Statistically Different
75
Responder Rate 13 lt 18 YRS
TREATMENT (N 55) OPTICAL CORRECTION (N 48)
TOTAL 14 (25) 11 (23)
AMBLYOPIA LEVEL
20/40 80 (N 33/29) 7 (21) 6 (21)
20/100-400 (N 22/19) 7 (32) 5 (26)

PRIOR AMBLYOPIA TREATMENT
Yes (N 38/28) 6 (16) 7 (25)
No (N 17/20) 8 (47) 4 (20)
N ()
Suggestive of Difference
76
Conclusions

• Amblyopic vision improves with optical correction
  alone in about ¼ of all 7 to 17 Year Olds and ½
  of 7 to 12 years olds with additional treatment.
• Amblyopic vision improves in 7 to lt 13 year old
  children but not 13 to lt 18 year olds who have
  been treated previously.
• All amblyopic eyes have remaining visual deficit.
• Persistence of effect after treatment cessation
  is unknown.

77
Amblyopia Treatment Study 4(ATS4)

• A Randomized Trial of
• Atropine Regimens for Treatment of
• Moderate Amblyopia in Children

78

• Study Objectives
• To compare daily versus weekend atropine
  (two-days) for moderate amblyopia (20/40 to
  20/80) in children 3 to lt7 years old
• To determine the maximum amount of improvement
  that could be achieved with these atropine
  schedules.

79

• Study Design
• A randomized, controlled, single-masked
  multi-center clinical trial
• 2 treatment groups
• Primary outcome Visual acuity at 4 months
• Secondary outcome Maximum visual acuity
  improvement

weekend atropine
daily atropine
80
Eligibility

• Age lt 7 years
• Able to measure visual acuity with single
  surrounded HOTV optotypes
• Strabismic and/or anisometropic amblyopia
• No amblyopia treatment in the past month and no
  more than 1 month of amblyopia treatment in the
  past six months

81
EligibilityVisual Acuity

• Amblyopic eye - 20/40 to 20/80
• Sound eye - gt 20/40
• Inter-eye acuity difference - gt 3 lines

82
Atropine Treatment

• weekend or daily atropine 1 solution was
  prescribed
• For patients in the daily atropine group, if the
  amblyopic eye acuity improved to be the same as
  or better than the sound eye acuity, atropine
  could be decreased to no less than twice per week

83
Visit Schedule

• 5-week visit
• Masked outcome visit at 4 months
• Amblyopic eye at 17 weeks, sound eye and
  binocularity at 19 weeks
• Additional visits at investigator discretion
• Partial responders returned every 8 weeks

84
Patient Characteristics
N168
Female 39
Caucasian 79
Age (mean) 5.3 years
Cause of Amblyopia
Strabismus 33
Anisometropia 41
Combined 23
Prior Amblyopia Treatment 18
85
Patient Follow-Up
86
Amblyopic Eye at 4 Months
Weekend atropine N83 Daily atropine N77
Mean improvement from baseline 2.3 lines 2.3 lines
Mean acuity at 4 months (Snellen approximation) 20/32-1 20/32-1
gt20/32 or gt3 line improvement from baseline 66 66
87
Amblyopic Eye at 4 Months
N92
N83
N77
Amblyopic Eye Visual Acuity Cumulative
Distribution
N89
gt20/16
gt20/20
gt20/25
gt20/32
gt20/40
gt20/50
gt20/63
gt20/80
gt20/100
gt20/125
gt20/160
4-month Amblyopic Eye Visual Acuity
88
Amblyopic Eye Mean Acuity at Each Visit
5 Weeks
Baseline
4 Months
20/32
20/32-1
20/32-1
20/401
20/40
20/40
Mean Visual Acuity Score
20/50
20/632
20/632
20/63
89
Acuity at Study Completion

• 20/25 or better OR equal to sound eye
• Daily - 39 (47)
• Weekend - 45 (53)
• Mean Amblyopic eye acuity
• Daily 0.23 logMAR (20/32-3)
• 2.3 lines of improvement
• Weekend 0.21 log MAR (20/32-1)
• 2.5 lines of improvement

90
Treatment Effect in Subgroups

• Effect of treatment was similar in subgroups
  based on
• Age
• lt5 years old, gt5 years old
• Cause of amblyopia
• strabismus, anisometropia, combined
• Baseline visual acuity in amblyopic eye
• lt20/63, gt20/50

91
Effect of Treatment on the Sound Eye

• A decrease in sound eye visual acuity of 2 or
  more lines at 4 months
• Weekend atropine - 2 patients (2.4)
• Daily atropine - 2 patients (2.6)
• Further Follow-up Testing
• One in each group same as or better than baseline
• One in each group 20/32 compared with 20/20 at
  baseline

92
Other adverse effects

• Light sensitivity (no treatment changes)
• Daily group 13 (16)
• Weekend group 25 (29)
• Facial flushing / fever
• 2 patients in daily group 1 stayed on treatment
  and 1 switched to homatropine

93
Ocular alignment

• 2 in daily and none in weekend developed gt 8D
  deviation
• 2 in daily, 3 in weekend had disappearance of a
  microstrabismus
• 10 developed new strabismus or a preexisting
  angle of strabismus that had increased by at
  least 10D
• 8 had their strabismus resolved or reduced by at
  least 10D

94
Amblyopia Treatment Index

• Both treatments were well tolerated.
• The subscale scores were similar between the
  groups on the adverse event and social stigma
  subscales.
• On the compliance subscale the weekend group was
  slightly worse.
• Median Score
• Subscale Weekend Daily
• Adverse Effects 2.00 2.00
• Difficulty with Compliance 2.10 2.00
• Social Stigma 2.00 2.00

95
Conclusions

• Weekend atropine appears to be as effective as
  daily atropine in treating moderate amblyopia in
  children 3 to lt 7 years of age
• A reduced frequency is another alternative
  treatment for amblyopia.
• The magnitude of the visual acuity improvement
  was similar to that seen for 2-hour and 6-hour
  prescribed patching regimens for moderate
  amblyopia.