Paediatric Vision Exam, Basic Course Lectures, Philippine General Hospital 2016

1. PGH Basic Course 2016
Basic Pediatric Vision Exam
Alvina Pauline D. Santiago, MD
Pediatric Ophthalmology & Strabismus

2. Vision Assessment
Preverbal Age Group

3. Visual milestones
• Birth Bright lights
• 7 days vestibulo-ocular reflex
• 3 mos transient fixation & following
• 6 mos fixation & following
even for distance
• 2-3 y 20/30
• 5-7 y 20/2

4. Vision Assessment
• Fixation pattern
• 3 mos: transient fix and follow
• 6 mos: fix and follow
– “CSM” : central, steady, maintained
– cover one eye
– start distance fixation

7. Fixation preference

8. Profound Amblyopia

9. Fixation Preference &
Visual Acuity
• Central, steady, maintained
CSM 20/20-20/30
• CS, maintained briefly 20/40-20/60
• CS, not maintained (NM)20/70-20/80
• C, NS, NM 20/100-20/200
• Not C, Eccentric </= 20/300

10. Optokinetic (Catford) drum
• Fast saccades
• May be calibrated
based on cycles per
degree

11. Preferential Looking
• Modified optokinetic
flag
• Teller acuity cards or
its derivative
• Facial targets

12. Teller acuity cards

13. Forced Choice
Preferential Looking Tests (FPLs)

14. School age child
• Not infants and toddlers
• Preschool 3-6 years
• Regular School 7-12
• Adolescent 13-18

15. Vision testing
• Quantifiable
• Depends on patient discrimination
• Depends on examiner ability to interpret
response
• Standard: Sloan linear acuity: optotype
• Psychophysical tests: test interpretation
subjective measured by patient’s ability to
communicate recognition to examiner

16. Preschool
• Short attention span
• Inability to sustain interest
• Language and communication barriers
• Cultural and social limitations

17. Preschool Tests
• Detection acuity tests
– Stycar graded balls (Sheridan 1973)
– Catford drum (Catford & Oliver 1973)
– Dot visual acuity test
• Recognition acuity test
– Direction oriented: Illiterate E, Landolt C
– Picture charts: Allen, Lea® Symbols
– Letter charts: Snellen, Sloan

18. Vision Assessment: 3-6 years
• Allen pictures: cultural
bias
• Sheridan Gardner or
HOTV/HOTEX
• Illiterate E / tumbling E / E
game
• Landolt C
• Lea® Symbols and
Numbers
• Snellen numbers, letters
– kids memorize!
• Sloan Letters http://www.keeler.co.uk/images/products/
nearvisionsheridan2_250x250.jpg

19. Visual Acuity Testing
• Test Charts
– HOTV / HOTEX
– Tumbling “E” Game
– Landolt C
– Picture Charts
Lea® Symbols
Allen picture cards

20. Illiterate/Preverbal Charts
Landolt C Tumbling E

21. HOTV Charts

22. Lea® Charts

23. Lea® Charts

24. Grating vs Snellen Acuity
• Grating acuity (cycles
per degree)
• Snellen acuity (visual
angle)
• Grating overestimates
Snellen

25. Limitations of Optotype Test
• Letter or number
acuity (e.g. Snellen
or Sloan) unreliable
before age 6-8
• Not all children will
know alphabet &
numbers
• Single optotypes
may overestimate
linear acuity
https://toddlerglasses.files.wordpress.com/2009/07/eye-charts-358x338-
allaboutvision.gif?w=300

26. Sloan letters
http://www.eyesfirst.eu/media/catalog/product/cache/1/
image/640x/040ec09b1e35df139433887a97daa66f/
5/2/52098_etdrs_tafel.jpg

27. Sloan vs. Snellen Charts
https://www.schoolhealth.com/blog/selecting-an-eye-chart-sloan-letters-or-snellen/

28. Normal Visual Development

29. Development of Visual Acuity

30. Susceptible Period
• Most sensitive first 2-3
years
• Decreases until age
6-7 years (12? 18?)
– complete visual
maturation
– retinocortical pathways
and visual centers
resistant to abnormal
visual input

31. 7-12 years
• Significant number still will not express
poor vision
• Easy to perform Sloan linear acuity testing

32. 13-18 years
• Will verbalize a visual problem

33. Vision Assessment
Non/Pre Verbal
OKN Drum FPLOKN Flag Teller

34. Vision Assessment
Picture Charts HOTV Snellen / Sloan
http://www.uniroma2.it/otticafp/vafig1.gif

35. Laser vision ;-)

36. Vision Assessment: Nystagmus
• Binocular near vision test
– allow patient to assume own distance
– test at standard near distance
– check head posture
– VA in forced primary
• Binocular distance vision
• Monocular distance & near vision

37. Vision Assessment: Nystagmus
• Monocular occlusion
– many will increase nystagmus
• Remote occlusion
• Sufficient fogging: know refraction!
• Neutral density filters
• AO vectograph testing
• Translucent occluder

38. Random dot stereograms
• 2 plates of randomly
displayed dots, one
plate to each eye
• Shape of figure
displaced horizontally
relative to other plate
• No monocular cues
• Normal may fail

39. Sensory Tests & Visual Acuity
Circles Seconds of Arc VA
9 40 20/25
8 50 20/30
7 60 20/40
6 80 20/50
5 100 20/60
4 140 20/70
3 200 20/80
2 400 20/100
1 800 20/200
Donzis 1974

40. Thank You!