Opthalmology for pediatricians

1. Ophthalmology for Pediatricians
Dr. Riyad Banayot

2. Background
Vision Disorders:
Fourth most common disability of childhood
Strabismus 3-4%
Amblyopia 2-3%
Refractive error 15-30%

3. Amblyopia
 Failure to develop normal visual acuity that
 Cannot be attributed directly to the effect of any structural
abnormality of the eye or the posterior visual pathway
 Types: - Strabismus (misalignment)
- Anisometropia (unequal refractive error)
- Deprivation (media opacity)
 Nearly all preventable or reversible with appropriate intervention

4. Amblyopia
Most common cause of monocular
blindness in pediatric population
Responsible for more unilaterally reduced
vision of childhood onset than all other
causes combined

5. Normal Development
Eye of term neonate is 1/3 of adult size
75% of infants are hyperopic (farsighted)
30% have astigmatism (refractive power not uniform
in all areas of cornea)
Immature fovea - limited acuity and fine color

6. Normal Development
Acuity at birth is 6/120
Age 6 months V/A is 6/6
Color vision improves by 3 months
Eye color evolves by 9-12 months
Iris is lightest in color at birth

7. Neuroanatomy
LGN synthesizes input from
both eyes
Lack of input from one eye
can damage stereo vision
and acuity (binocular vision)
“Critical Period”

8. Critical Period
“Period” early in
infancy when
the visual
system is
sensitive to
deprivation
0
10
20
30
40
50
60
70
80
90
100
0 0.5 1 2 3 4 5 6 7 8 9 10
Age (yrs)
% Vision

9. Critical Period
1st phase:
- Birth to 10 months
- Rapid development
- Highly susceptible to insult
- Responsive to treatment
2nd phase:
- 1 – 9 yrs
- Slower change
- Rehabilitation prognosis poorer
0
10
20
30
40
50
60
70
80
90
100
0 0.5 1 2 3 4 5 6 7 8 9 10
Age (yrs)
% Vision

10. Critical Period
Congenital cataracts must be detected and
removed early !
Early surgery has better prognosis

11. Age Appropriate Screening
American Academy of Pediatricians (AAP)

12. AAP Screening Guidelines:
Timing of Exam:
“Age-appropriate” screen at all visits, starting
in newborns
Formal ophthalmologic examination for all
infants at-risk
Formal screening evaluation starting at age 3
- 4 years

13. High Risk for Amblyopia
BW < 2000 g (prevalence 20%)
Developmental Delay (TORCH, Down
Syndrome, idiopathic)
Parent or older sibling with amblyopia
Need Eye Exam Before Age 1 year

14. AAP Screening Guidelines:
History:
“Does your child seem to see well?”
“Does your child seem to hold objects
unusually close to face?”
“Do the eyes seem cross?”

15. AAP Screening Guidelines:
Vision Charts:
3-4 years: Picture tests
> 4 years: Snellen letters or numbers,
tumbling E, letter-matching test

16. SnellenSnellen

17. Tumbling ETumbling E

18. AAP Screening Guidelines:
Birth to 2 Years of Age
Eyelids and orbits
External examination
Motility
Eye muscle balance
Pupils and Red Reflex

19. Congenital Glaucoma
Congenital Glaucoma:
Note larger right corneal diameter

20. Congenital Glaucoma
Congenital Glaucoma:
Note larger right corneal diameter

21. Congenital Cataract

22. Corneal Light Reflex
Normal

23. Corneal Light Reflex
Esotropia

24. Corneal Light Reflex
Exotropia

25. Corneal Light Reflex
Hypertropia

26. Ocular Misalignment
Can be physiologic in first 4 months of life,
but usually resolves by 2 months
Newborns can have disconjugate eye
movements
Early treatment for strabismus
Must be corrected before age 2 for stereo
vision to develop

27. Pseudostrabismus

28. AAP Screening Guidelines:
2 years to 4 years
Same as “birth to 2 yrs”
Also should try vision testing
If unable to assess, should refer to pediatric
ophthalmologist

29. AAP Screening Guidelines:
5 years and older
Formal vision testing
If unable to assess after 2 attempts or if
abnormality found should refer to
ophthalmologist

30. AAP Screening Guidelines:
Muscle Imbalance Testing
Strabismus, manifest or latent imbalance of
extraocular muscles
Manifest = “Tropia”
Latent = “Phoria”

31. AAP Screening Guidelines:
Muscle Imbalance Testing
Inward (nasal) = “Eso”
Outward (temporal) = “Exo”
Vertical = “Hyper”

32. AAP Screening Guidelines:
Muscle Imbalance Testing
 “E” = esophoria
 “ET” = esotropia
 “X” = exophoria
 “XT” = exotropia
 “H” = hyperphoria
 “HT” = hypertropia
Cover / uncover test

33. Refractive Errors
Affects 20% of population before late teens
Myopia (nearsighted) common
Hyperopia (farsighted)
Astigmatism - unequal curvature of refractive
surface
Anisometropia - unequal refractive errors in
each eye
All can possibly cause amblyopia if untreated

34. Treatment
Correct underlying cause (cataract,
strabismus, refractive error)
Strabismus corrected surgically
For amblyopia due to non-surgical causes,
treatment is usually with “Occlusion Therapy”

35. Patch vs. Atropine
Prospective randomized trial by National Eye
Institute
Early difference at 3 months favoring patch
No difference at 6 months
Atropine accepted better by parents
No known long-term effect of atropine, i.e. no
“reverse amblyopia”

36. Take Home Message:
Vision disturbances are common
Amblyopia is bad but preventable
Amblyopia can be due to refractive error, strabismus, or
other causes
Exam should be age-appropriate
High-risk babies need early care
When in doubt, refer!