simplifying ocular movements.

1. By Dr.Sandhya
ANATOMY AND
OCULAR MOVEMENTS

2. Eyelids
Eyelashes
Canthi
Palpebral fissure
Caruncle
Glands
External appearance of the eye

3. ADNEXA
 EYELIDS
 ORBIT
 EXTRAOCULAR MUSCLES
 TEARS AND DRAINAGE APPARATUS

4. EYELIDS
 The eyelids are the
moving folds of skin that
cover the outer portion of
the eyeball.
 Protect the eye from
injury and from light

5. ORBIT
 The orbit is the bony cavity in the skull that houses the
globe, the extra ocular muscles, the blood vessels and
the nerves all of which are cushioned by layers of fat.
The globe is situated within the bony orbit in such a
way that it is protected from major injury by a rim of
bone.

8. EXTRAOCULAR MUSCLES
 The muscles that control the movement of
the globe are called extra ocular muscles to
distinguish them from the muscles inside the
eyeball.
 The 6 extra ocular muscles are named by the
positions in relation to the globe
 The positions determine the direction of
movement of the eyeball when the muscles
contract.

9. LACRIMAL APPARATUS

10. OCULAR
MUSCLES
EXTRA OCULAR
VOLUNTARY INVOLUNTARY
INTRAOCULAR
CILLIARY
MUSCLES

11. INVOLUNTARY VOLUNTARY
• SUPERIOR TARSAL MUSCLE
• INFERIOR TARSAL MUSCLE
• MEDIAL RECTUS
• LATERAL RECTUS
• SUPERIOR RECTUS
• INFERIOR RECTUS
• INFERIOR OBLIQUE
• SUPERIOR OBLIQUE
• LEVATOR PALPABERAL
SUPERIORIS

14. NERVE SUPPLY
 ALL-3,
 SO4
 LR6

15. MUSCLES PRIMARY ACTION SECONDARY ACTION TERTIARY ACTION
MR ADDUCTION - -
LR ABUDUCTION - -
SR ELEVATION INTORSION ADDUCTION
IR DEPRESSION EXTORSION ADDUCTION
SO INTORSION DEPRESSION ABDUCTION
IO EXTORSION ELEVATION ABDUCTION
SIN
RADD

17. LAWS OF OCULAR MOTILITY
 Agonist
 Any particular EOM producing specific ocular movement .
 Ex. Right LR for right eye abduction .
 Synergists
 Muscles of the same eye that move the eye in the same direction
 Ex. Right SR and right IO for right eye elevation .

18.  Antagonists
 A pair of muscles in the same eye that move the eye in
opposite directions.
 Ex. Right LR and right MR.
 Yoke muscles ( contralateral synergists)
 Pair of muscles, one in each eye, that produce
conjugate ocular movements.
 Ex. Right LR and left Mr in dextroversion.

20. Ocular motolity
Binocular movement
Versions( same direction) Vergence( opposite direction)
Uniocular movement
Adduction
Abduction
Elevation
Depression
Intorsion
Extorsion
Dextroversion
Levoversion
Supraversion
Infraversion
Dextrocyloversion
levocycloversion
Convergence
divergence

21. UNIOCULAR MOVEMENT

22. BINOCULAR MOVEMENT OF EYE

23. VERGENCES
NORMAL

24. HERING’S LAW OF EQUAL
INNERVATION
 An equal and simultaneous innervation flows from
the brain to a pair of yoke muscles which contracts
simultaneously in different binocular movement.
 Ex. Right LR and Left MR during dextroversion.
 Applies to all normal eye movements.

25. SHERRINGTON’S LAW OF
RECIPROCAL INNERVATION
 States that increased innervation to a contracting
agonist muscle is accompanied by reciprocal inhibition
of its antagonist.
 Ex. During detroversion there is increased innervation
to right LR and left MR accompanied by decreased flow
to Right MR and left LR.