1. Padmaja Sudhakar MD Asst Professor Neurology University of Kentucky
How do the eyes move?
Padmaja Sudhakar MD
Asst Professor Neurology
University of Kentucky

2. Welcome to the efferent system

3. ANATOMY OF THE ORBIT

4. ANATOMY OF ORBIT Seven bones make up the orbit
Roof - frontal bone & the lesser wing of sphenoid
Floor – maxilla, zygomatic bone, palatine bone
Medial wall - maxilla, lacrimal bone, ethmoid , sphenoid
Lateral wall - zygomatic, greater wing of sphenoid
Medial walls are parallel, lateral walls form an angle of 900

5. ANATOMY OF ORBIT Superior Orbital Fissure/Orbital Apex
Contiguous with the cavernous sinus
Transmits– III, IV, VI, V1, sympathetics, superior ophthalmic vein.
Annulus of Zinn – origin of recti muscles
Optic canal transmits the optic nerve & ophthalmic artery

6. ANATOMY OF EXTRAOCULAR MUSCLES

7. EXTRAOCULAR MUSCLES Six extraocular muscles
4 recti- superior, inferior, medial, lateral
2 obliques – superior, inferior
Inferior oblique- thinnest
Medial rectus – largest

8. EXTRAOCULAR MUSCLES
Recti run forward within sheaths , pierce the posterior tenon’s capsule & insert on the anterior sclera at points variably posterior to the corneal limbus – Spiral of Tillaux
Tenon’s capsule - connective tissue that surrounds the eyeball & extends to the optic nerve.

9. EXTRAOCULAR MUSCLES Superior oblique
Origin – Trochlea (pulley like structure)
Runs anteriorly in the superior medial orbit to trochlea
Tendon reverses direction
Inferior oblique – anterior inferior medial periorbita near lacrimal fossa
Both obliques insert on the posterior lateral aspect of globe behind the equator

10. EXTRAOCULAR MOVEMENTS
Ductions - Monocular eye movements
Versions - Movement of both eyes in the same direction
Vergences are movements of the eyes in opposite directions
Yoke muscles are the primary muscles in each eye that accomplish a given version (eg, for right gaze, the right lateral rectus and left medial rectus muscles)

11. ACTIONS OF EOMS Medial rectus
Adducts the eye or moves eye towards the nose
Lateral rectus
Abducts the eye or moves the eye horizontally to the outside

12. ACTIONS OF EOMS Superior rectus Primary action –elevation
Secondary action (globe adducted) – intortion, adduction
Inferior rectus
Primary action – depression
Secondary action (globe adducted)- extortion, adduction

13. ACTIONS OF EOMS Superior oblique Primary action – intortion, abduction
Secondary action (globe adducted) – depression
Inferior oblique
Primary action – extortion, abduction
Secondary action (globe adducted)- elevation

14. INNERVATION 3rd cranial nerve
Superior division– levator, superior rectus, medial rectus
Inferior division -inferior rectus, inferior oblique
4th cranial nerve – superior oblique
6th cranial nerve – lateral rectus

15. ANATOMY OF THE CAVERNOUS SINUS

16. CAVERNOUS SINUS Complex plexuses of veins in the dura
Located lateral to the sphenoid sinus
Extends from the SOF to the apex of the petrous temporal bone
Lateral wall of the sinus – III, IV & V1 nerve
Internal carotid artery ,VI nerve (lateral) run in the sinus

17. PATHOLOGY

18. DIPLOPIA Reported as double vision or blurred vision
Does diplopia resolve when one eye is covered?
Monocular vs binocular
Is the diplopia horizontal,vertical or oblique?
Is it same in all fields of gaze (comitant) or vary with gaze direction (incomitant)
Is it constant, intermittent or variable?

19. DIPLOPIA
Monocular- optical – refractive error, cataract, rarely maculopathy
Binocular
Orbital Mass
Muscle
Neuromuscular junction
Nerve
Cavernous sinus

20. ORBITAL MASS Intraconal Primary Cavernous hemangioma
Optic nerve glioma
Optic nerve meningioma
Rhabdomyosarcoma
Orbital varices
Metastatic lesions
Breast
Lung
Prostate
Neuroblastoma

21. ORBITAL MASS Extraconal Superior orbit (roof/frontal sinus)
Dermoid tumor
Mucocoele (frontal sinus)
Orbital encephalocoele
Fibrous dysplasia
Lacrimal gland tumors

22. ORBITAL MASS Extraconal Inferior orbit (maxillary sinus/floor)
Maxillary sinus mucocoele
Fungal sinusitis
Primary tumor (benign or malignant)
Secondary tumor

23. ORBITAL MASS Extraconal Medial orbit (ethmoid /sphenoid sinus)
Rhabdomyosarcoma
Carcinoma of sinus
Mucocoele

24. ORBITAL MASS Extraconal Lateral orbit (pterygopalatine fossa)
Metastasis
Pseudotumor of orbit
Hemangioma
Meningioma
Rhabdomyosarcoma
Arteriovenous malformations
Encephalocoele
Fibrous dysplasia
Trauma with hemorrhage

25. MUSCLE Mechanical limitation of range of eye movements
Thyroid associated orbitopathy
Orbital myositis
Orbital trauma
Post – surgery restriction (cataract extraction)
Genetic extraocular myopathy
Congenital fibrosis syndrome
Neoplastic infiltration
Brown syndrome

26. NERVE
3rd cranial nerve
Superior division – Levator, superior rectus, medial rectus
Inferior division –inferior rectus, inferior oblique
4th cranial nerve – superior oblique
6th cranial nerve – lateral rectus
Apex syndrome – CN 2, 3, 4, 6 all together

27. CAVERNOUS SINUS CN 3, 4, 6, V1, and sympathetics
When limited to 3, 4, 6 difficult to distinguish cavernous sinus from orbital apex
Fifth nerve involvement – facial hypoaesthesia
Sympathetic involvement - Horner’s syndrome

28. NEUROMUSCULAR JUNCTION
Myasthenia Gravis
Fluctuating /variable ptosis or diplopia, ductional deficits
Bilateral orbicularis weakness

29. A. 6th nerve palsy
B. INO ?
C. Myasthenia
D. Duanes Type 1 29

30. DUANES RETRACTION SYNDROME TYPE 1
Congenital absence of 6th nerve/nucleus
Orthophoric in primary
Esotropic on lateral gaze with limited abduction
No diplopia despite misalignment 30

31. DUANES RETRACTION SYNDROME TYPE 1
Palpebral fissure narrows and globe retracts on adduction

32. ?
A. Myasthenia
B. INO
C. Duanes Type 2
D. 3rd nerve palsy 32

33. DUANES RETRACTION SYNDROME TYPE 2
Orthophoric in primary
Exotropic on lateral gaze and limited
adduction
Palpebral fissure
narrows and
globe retracts on adduction
No diplopia despite misalignment 33

34. ? A. Gaze palsy B. 1 ½ syndrome C. Myasthenia gravis D. Duanes Type 334

35. DUANES RETRACTION SYNDROME TYPE 3
Orthophoric in primary
Limited abduction and adduction
Palpebral fissure narrows and
globe retracts on adduction
No diplopia despite misalignment 35

40. ?
A. MG
B. Duanes Syndrome
C. CPEO
D. Mobius

41. CHRONIC PROGRESSIVE EXTERNAL OPHTHALMOPLEGIA
Bilateral ptosis and ophthalmoplegia
Progresses over years
Can be asymmetric
Mitochondrial myopathy
Check EKG
Review MR 41

42. ? A. Myasthenia gravis B. Multiple sclerosis C. Orbital process
D. Tolosa-Hunt 42

43. EOM METASTASIS FROM BREAST CANCER
Review the PMH
Orbital signs are not always present with an orbital process

44. ?
A. Myasthenia
B. 3rd nerve palsy
C. TED
D. Aberrant Regeneration 44

45. THYROID EYE DISEASE

46. ?
A. CPEO
B. 3rd nerve palsy
C. Myasthenia
D. Orbital Process

47. SLEEP TEST – take a nap while you wait for the doctor

49. THANKYOU