This document discusses strabismus and amblyopia. It covers the anatomy of the extraocular muscles, their actions and movements. It describes laws of ocular motility like Hering's law and Sherrington's law. The document outlines various tests for assessing vision and eye alignment in infants and children, including visual acuity testing, fixation preference testing, ocular motility evaluation, and motor function testing techniques like cover tests. It discusses conditions like amblyopia, strabismus types, and third nerve palsy.

1. Strabismus & Amblyopia
Alvina Pauline D. Santiago, MD
Pediatric Ophthalmology & Strabismus
Revised Dec 2014 ASMPH Y7

2. Anatomy of
Extraocular Muscles
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3. EOM Mechanisms
! Actions of muscles
! Ductions & Versions
! Vergence movements: convergence,
divergence
! Hering’s & Sherrington’s laws
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4. Orbital apex
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5. Medial rectus
www.wikipedia.org
adduction

6. Lateral rectus
www.wikipedia.org
abduction

7. Inferior rectus
! depressor
! adducts
! excyclotorsion
www.wikipedia.org

8. Superior rectus
! elevates
! adducts
! incyclotorts
www.wikipedia.org

9. Superior oblique
! incyclotorts
! depresses
! abducts
www.wikipedia.org

10. Inferior oblique
! excyclotorts
! elevates
! abducts
www.wikipedia.org

11. EOM Movements
! Duction: rotation from one eye
! Versions: movement of both eyes from
primary position (straight) to secondary
position
! Vergence: simultaneous ocular
movements
! convergence: nucleus of Perlia (midbrain)
! divergence: midbrain near acoustic nerve nucleus
08 January 2010 ASMPH Y7

12. Ocular Motility

13. Laws of Ocular Motility
! Hering’s law of equal innervation
! explains conjugate eye movements
! Yoke muscles receive equal innervation
! Sherrington’s law of reciprocal innervation
! concerned with coordination of muscle pairs of one eye
! when agonist contracts, there is inhibition of its direct antagonist
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14. Yoke muscles: Hering’s Law
RLR
LMR
RMR
LLR
RSR
LIO
RIR
LSO
RIO
LSR
RSO
LIR

15. Antagonist Muscles: Sherrington’s Law
RSR
(-) RIR
RLR
(-) RMR
RIR
(-) RSR
RIO
(-) RSO
RMR
(-) RLR
RSO
(-) RIO

16. Vision Assessment
Preverbal Age Group
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17. Visual acuity testing
• Evaluating fixation and preference
• Using Allen cards or other preverbal test
charts
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18. Visual milestones
• Birth Bright lights
• 7 days vestibulo-ocular reflex
• 3 mos transient FF
• 6 mos FF even for distance
• 2-3 y 20/30
• 5-7 y 20/20
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19. Vision Assessment
• Fixation pattern
• 3 mos: transient fix and follow
• 6 mos: fix and follow
– “CSM” nomenclature
– cover one eye
– start distance fixation
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20. ASMPH Y7

21. ASMPH Y7

22. Fixation preference
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23. Fixation Preference
Son: Left Left Left None
TEXT TEXT TEXT TEXT
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24. Profound Amblyopia
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25. 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
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26. Vision Assessment
Non/Pre Verbal
OKN Drum OKN Flag FPL Teller
08 January 2010 ASMPH Y7

27. Visual Acuity Testing
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• Test Charts
– HOTV / HOTEX
– “E” Game
– Landolt C
– Picture Charts

28. Vision Assessment
Picture Charts HOTV SNELLEN
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29. Strabismus Testing
Tests of Ocular Alignment
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30. Motor Testing
• Ocular rotations
• Measuring the deviation
• Anomalous head posture
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31. Ocular Rotations
• Duction: monocular
• Version: binocular
• Hering’s law
• Sherrington’s law
• Alert to pattern deviations: e.g., A, V
• Grading scheme:
– e.g., inferior oblique & superior oblique
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32. Ocular Motility Evaluation
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RLR
LMR
RMR
LLR
RSR
LIO
RIR
LSO
RIO
LSR
RSO
LIR

33. Ocular Rotations: Yoke muscles
Cardinal gaze positions
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RLR
LMR
RMR
LLR
RSR
LIO
RIR
LSO
RIO
LSR
RSO
LIR

34. (L) Inferior oblique dysfunction
+4 +1
-4 -1
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35. (R) Superior oblique
dysfunction
+4 +1
-4 -1
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36. Ocular misalignment
• Hirschberg’s light reflex test
• Bruckner’s red orange reflex test
• Alternate prism cover test
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37. Hirschberg’s Corneal Reflex
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38. Hirschberg’s Corneal Reflex
Mom: straight
Son: RET RET RXT PseudoET
TEXT TEXT TEXT TEXT
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39. Pseudostrabismus
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40. Head posture, Anomalous?
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41. Anomalous head posture
• Measure in non
preferred head
posture
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42. Motor Testing
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• Light reflex tests
• Cover tests
• Other tests
– wear correction
– no prisms

43. Motor Testing: Light Reflex Tests
• Bruckner test
• Hirschberg light reflex
• Krimsky/modified Krimsky
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44. Bruckner Test
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® Ametropia
® strabismus

45. Hirschberg’s Light Reflex
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• 3.5 mm pupil:
– 15 degrees at pupil
edge
– 30 degrees between
limbus and edge of
pupil
– 45 degrees at limbus

46. Krimsky vs Modified Krimsky
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– in front of deviating
eye (modified
Krimsky)
– underestimates
true angle
– better at near

47. Motor Testing: Cover Tests
• Primary gaze
• Right and left gaze
• Up and down gaze
• Right and left head tilt
• Near: primary and down gaze
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48. Cover Tests
• Requirements:
– appropriate correction
– no prisms vs. prisms
– accommodative target
– distance:
• 6 m: 1/8 D of accommodation
• > 6 m: X(T)
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49. Techniques in Finding Strabismus
• Bruckner test
• Spielmann
translucent occluder
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50. (L) Superior oblique palsy
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51. Direct Ophthalmoscope View:
Fundus Torsion
Excyclorotation Incyclorotation
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52. Paralytic Exotropia:III nerve palsy
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53. Inferior oblique dysfunction
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54. Bruckner (Red Orange Reflex)
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55. Amblyopia
Pediatric Eye Disease Investigator Group
(PEDIG)
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56. Thank You!
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