This document provides an overview of ocular motility and strabismus. It defines key terms like strabismus, heterophoria, heterotropia, and discusses the extraocular muscles and their actions. It also describes tests used to examine eye alignment and motility, including the cover test, Hirschberg test, and Krimsky test. Treatment options discussed include amblyopia management, strabismus surgery using muscle resections and recessions.

1. OCULAR MOTILITY
DEPARTMENT OF
OPHTHALMOLOGY
FATIMA COLLEGE OF
MEDICINE

2. Introduction
• Under normal conditions, the image of the
object of regard falls simultaneously on the
fovea of each eye, when the eyes are in
perfect alignment. Any deviation from
perfect ocular alignment is known as
“STRABISMUS.”

3. Recti Muscles

4. Oblique Muscles

5. Yoke Muscles

6. DUCTION
• Monocular rotations with no consideration
of the position of the other eye
– Adduction : Inward rotation
– Abduction : Outward rotation
– Elevation or Supraduction : Upward rotation
– Depression or Infraduction : Downward
rotation

7. FUSION
• Formation of one image from the two
images seen simultaneously by the two eyes
– Motor fusion (EOM control)
– Sensory fusion (visual sensory integration of
the brain)

8. HETEROPHORIA
• Latent deviation of the eyes held straight by
binocular vision
– Esophoria : tendency to turn inward
– Exophoria : tendency to turn outward
– Hyperphoria : tendency to deviate upward
– Hypophoria : tendency to deviate downward

9. Heterotropia/Strabismus
• Manifest deviation of the eyes that can not
be controlled by binocular vision
– Esotropia : convergent manifest deviation
– Exotropia : divergent manifest deviation
– Hypertropia : manifest deviation of one eye
upward
– Hypotopia : manifest deviation of one eye
downward

10. Definition of Other Terms
• Orthophoria : absence of any tendency of
either eye to deviate when fusion is
suspended
• Primary deviation : deviation measured
with the normal eye fixating and the eye
with the paretic muscle deviating
• Secondary deviation : deviation measured
with the paretic eye fixing and the normal
eye deviating

11. Definition of Terms
• Prism Diopter - a unit of angular
measurement used to characterize ocular
deviations
• Torsion : rotation of the eye about its
anteroposterior axis
– Intorsion : 12 o clock meridian turning toward
the midline
– Extorsion : 12 o clock meridian turning away
from the midline

12. Definition of Terms
• Conjugate Movement : Movement of the
two eyes in the same direction at the same
time
• Vergences : Movement of two eyes in
opposite directions
– Convergence : The eyes turn inwards
– Divergence : The eyes turn outwards

13. Synergistic and Antagonistic
EOMS
• Sherrington’s Law - There is a reciprocal
innervation of antagonistic muscles.
– The antagonist relaxes as the agonist contracts
• eg. The right eye’s right gaze would involve a
contraction of the right lateral rectus and a
relaxation of the right medial rectus

14. YOKE MUSCLES
• Hering’s Law : for movements of both eyes
in the same direction, the corresponding
agonist muscles receive equal innervation
– e.g. When gazing right the right lateral rectus
contracts along with the left medial rectus

15. Definition
• Concomitant Strabismus : the degree of
deviation is equal in all fields of gaze
• Incomitant (paretic) Strabismus : the degree
of deviation is unequal in different fields of
gaze

16. Concomitant Strabismus

17. Incomitant Strabismus

18. Overshoot in Incomitant
Esotropia

19. Amblyopia
• Vision loss without any organic or anatomic
ocular pathology
– Strabismic
– Refractive
– Deprivation

20. Sensory Changes in Strabismus
• Diplopia
• Suppression
• Amblyopia
• Anomalous Retinal Correspondence
• Eccentric Fixation

21. History
• Family History
• Age at Onset
• Type of Onset (gradual, sudden,
intermittent)
• Type of Deviation (comitant or incomitant)
• Fixation (one eye or alternating)

22. EOM Function

23. Ocular Examination
• Visual acuity adapted for age
• Determination of Refractive Error
• Inspection

24. E Chart

25. Picture Chart

26. Leukocoria

27. Exotropia

28. Esotropia

29. Examination Specific for Ocular
Motility
• Cover Test
• Uncover Test
• Alternate Cover Test
• Prism plus Cover Test
• Maddox Rod Test
• Hirschberg Test
• Krimsky Test
• Gaze Positions
• Convergence Measurement

30. Cover Test

31. Cover Test

32. Cover-Uncover Test

33. Latent Exophoria

34. Hirschberg Test

35. Hirschberg’s Test

36. Krimsky Test

37. Patient’s View in Maddox Rod
Testing

38. Treatment of Amblyopia
• Occlusion Therapy
• Refraction
• Orthoptic Exercises

39. Surgical Management of
Strabismus
• Resection - strengthening procedure
• Recession - weakening procedure

40. Squint Surgery

41. Thank You