Ocular motility and gaze

1. Amr Hassan, MD, FEBN Associate professor of Neurology - Cairo University Ocular motility, gaze,and Nystagmus

2. AGENDA • 3rd,4th, 6th nerves • Extraocular muscles • How to examine for ocular motility • Ophthalmoplegia • Diplopia and related disorders • Gaze pathway • How to examine for gaze • Gaze palsy • Types of eye movements • How to examine for EM • Nystagmus and non nystagmus ocular oscillation

4. Oculomotor nerve

5. • The oculomotor nerve originates from 3 nuclei:  Motor neurons arise from the oculomotor nucleus  Parasympathetic fibers arise from Edinger- Westphal nucleus.  Perlia nuclei in the midbrain. Oculomotor nerve

6. Oculomotor nerve

7. Oculomotor nerve

8. Oculomotor nerve

9. • The nucleus of origin of the oculomotor nerve. 1. Posterior dorsal nucleus. 1’. Posterior ventral nucleus. 2. Anterior dorsal nucleus. 2’. Anterior ventral nucleus. 3. Central nucleus. 4. Nucleus of Edinger and Westphal. 5. Antero-internal nucleus. 6. Antero-external nucleus. 8. Crossed fibers. 9. Trochlear nerve, with 9’, its nucleus of origin, and 9", its decussation. 10. Third ventricle. M, M. Median line. Oculomotor nerve

10. Oculomotor nerve • The nerve passes through the superior orbital fissure to reach the orbit. • The motor component of the nerve divides into a superior and inferior division: – The superior division supplies the levator palpebrae superioris and superior rectus muscles. – The inferior division supplies the medial rectus, inferior rectus and inferior oblique muscles.

11. Oculomotor nerve

12. Oculomotor nerve The parasympathetic component of the oculomotor nerve travels with inferior division to innervate  Ciliary muscle  Constrictor pupillae muscle

14. • The trochlear nerve has only a somatic motor component which innervates the superior oblique muscle of the contralateral orbit. • The nucleus of this nerve lies in the lower part of the midbrain. Trochlear nerve

15. Abducent Nerve

16. Cavernous sinus

19. Extraocular muscles

24. • the superior oblique muscle which turn the eye inwards & downwards (Thus help reading and descending the stairs). SO4

25. Action of Extraocular muscles

31. Lesions of the oculomotor nerve • External ophthalmoplegia • Internal ophthalmoplegia NB: compression: early mydriasis and lost light reflex infarction: pupillary reflex intact Lesions of the oculomotor nerve

32. Partial Complete Ptosis : unilateral

33.  O C D  Distribution: Uni/Bilateral. Symm/Asymmetrical Simultaneous/ Sequential Partial / complete  Painful or not.  Limitation of ocular motility( double vision)  Diminution of vision.  Local eye manifestations: (photophobia, lacrimation, exophthalmos, red eye) Ptosis

34. (A) Asymmetrical ptosis (B) application of ice; (C) improvement of ptosis Positive ice test in myasthenia gravis.

35. Ptosis : frontalis overaction

36. Block the action of frontalis to differentiate between partial and complete ptosis. Ptosis : frontalis overaction

37. Myotonic dystrophy Characterstic facies, frontal baldness and left exotropia Ptosis : Bilateral, partial

38. (A) Severe bilateral ptosis with defective upgaze; (B) defective downgaze; (C) defective left gaze; (D) defective right gaze Progressive external ophthalmoplegia

39. Lesions of the Trochlear nerve

40. Lesions of the Trochlear nerve

41. Park-Bielschowsky three-step test ‫األربعه‬ ‫دور‬

42. Park-Bielschowsky three-step test ‫النهائي‬

43. Park-Bielschowsky three-step test ‫البطل‬

44. Abducent nerve palsy Trochlear nerve palsy

47. Assessment of the Patient with Diplopia History ■ Define symptoms. ■ Effect of covering either eye? ■ Horizontal or vertical separation of the images? ■ Monocular? ■ Effect of distance of target (worse at near or far)? ■ Effect of gaze direction? ■ Tilting of one image? Observation ■ Head tilt or turn? (“FAT scan”) ■ Ptosis (fatigue)? ■ Pupil size? ■ Proptosis? ■ Spontaneous eye movements? Eye Examination ■ Visual acuity (each eye separately, and binocularly if primary position nystagmus present) ■ Versions (pursuit, saccades) ■ Convergence (does miosis occur?) ■ Ductions ■ Ocular alignment (muscle balance) in the “forced primary position” ■ Pupils ■ Lids (examine palpebral fissures, levator function, fatigue) ■ Vestibulo-ocular reflexes (doll’s eye reflex) ■ Bell phenomenon ■ Optokinetic nystagmus

49. The ability of the eyes to move symmetrically and synchronously in the same direction, horizontally or vertically is termed “ cojugate” gaze. Gaze

51. Gaze

52. Horizontal Gaze

53. Horizontal Gaze

54. UPWARD GAZE Rt. Lt. Frontal eye field 8 Occipital eye field III Thalamus Pre-tectal nucleus MLB SR IOSR IO

56. DOWN GAZE III Rt. Lt. Frontal eye field 8 Occipital eye field Red Nucleus MLB IRIR

58. Brainstem supranucler motor centers

60. How to examine for gaze

65. It is the inability to move both eyes simultaneously either horizontally or vertically. Types of Gaze palsy: 1. Horizontal gaze palsy 2. Vertical gaze palsy Gaze palsy

66. Looking to RIGHT Nystagmus on abducting eye Failure of adduction with NORMAL III Cr.N : INO: Internuclear Ophthalmoplegia

67. INO :MLF Lesion

68. • Demyelination • Vascular disease • Tumours of the brainstem and 4th ventricle • Trauma • Encephalitis • Hydrocephalus • Progressive supranuclear palsy • Drug-induced • Miller fisher syndrome • Wernick s’ encephalopathy INO : Causes

69. Looking to LEFT VI Cr.N palsy 11/2: One –and – half syndrome

70. VI Cr.N palsy: One Looking to RIGHT Failure of adduction with nystagmus on the abducting eye: Ant.INO: half. 11/2: One –and – half syndrome

71. 71 One and half syndrome: MLF + PPRF Lesion

72. 72 One and Half syndrome: Midbrain infarction !

73.  Signs: • Upward gaze palsy. • Defective convergence. • Large pupils light-near dissociation. • Lid retraction (Collier sign). • Convergence-retraction nystagmus.  Causes: a In children: aqueduct stenosis, meningitis and pineal body tumer b In young adults: demyelination, trauma and arteriovenous malformations. c In the elderly: midbrain vascular accidents, mass lesions involving the periaqueductal grey matter (pineal body tumer )and posterior fossa aneurysms. Parinaud (dorsal midbrain) syndrome

74. MR sagittal view shows a pinealoma and a dilated 3rd ventricle Parinaud (dorsal midbrain) syndrome

75. • Supranuclear gaze palsy, which initially primarily affects downgaze. • As the disease progresses, upgaze is also affected. • Horizontal movements subsequently become impaired and eventually global gaze palsy develops. • Pseudobulbar palsy. • Extrapyramidal rigidity, gait ataxia and dementia. PSP

77. Eye movements

78. Eye movements

79. • Saccades are rapid, brief conjugate eye movements that are characterized by their ballistic nature and high velocity (400–800°/s). • These redirect our line of gaze while trying to acquire a new object of interest. Saccades

80. • Latency: the length of time between the onset of target to the onset of saccade. • Gain: ratio of the initial saccade amplitude to the final target saccade amplitude • Peak velocity • Final eye position. Saccades metrics

81. Pathway of voluntary saccades

82. Frontal eye field Para-Pontine Reticular Formation (PPRF) Ocular Motor Nuclei Cr.N III, IV, VI Posterior eye field Superior Colliculus Caudate Substantia Nigra Pathway of voluntary saccades

83. • Executed following an internal decision to look in a particular direction like glancing at the clock on the wall after a long tiring day at work. • Voluntary saccades are further divided into memory-guided, predictive, endogenous saccades, and antisaccades Voluntary saccades

84. Pathway of voluntary saccades

85. A pursuit is slow, steady eye movement to track an object. Pursuit System

87. Pathway of Pursuit

88. Anatomical scheme for smooth Pursuit eye movement Striate Cortex (LGB) Extra-Striate Visual Areas MT: middle temporal, MST:medial sup.temporal, PP: posterior parietal cortex Dorso-Lateral PONTINE NUCLEI CEREBELLUM: Flocculus& Dorsal vermis Vestibular Nuclei Ocular Motor Nuclei Cr.N III, IV, VI

90. How to examine for Saccade

92. THANK YOU amrhasanneuro@kasralainy.edu.eg

Ocular motility and gaze

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