undergraduate lecture

1. NEURO-OPHTHALMOLOGY
Mohamed Abdelzaher MD, FRCS

2. Topics
- Pupil
- Ocular motor system
- Visual system
- Visual fields

3. The involuntary window into our state of emotional thought.

4. Light Reflex
• Stimulus: Light
• Receptors: Rods & Cones
• Afferent: Optic nerve, chiasm,
anterior 2/3 of optic tract, pre-tectal
nucleus
• Center: Edinger Westphal nucleus
(III)
• Efferent: III nerve
(Parasympathetic root of ciliary
ganglion)
• Response: Miosis

5. Near Reflex
• Stimulus: changing sight from far to
near object
• Receptors: Rods & Cones
• Afferent: Optic nerve, chiasm, optic
tract, LGB, optic radiation, occipital
cortex, frontal cortex, internal capsule
• Center: Edinger Westphal nucleus (III)
• Efferent: III nerve (Parasympathetic
root of ciliary ganglion + nerve to MR)
• Response: Miosis + Convergence +
Accommodation

6. How to perform
light reflex:
• Dim room
illumination
• Ask the patient
to look at a far
object
• Use bright light

7. Afferent Pupillary Defect III nerve palsyEfferent Defect, Parasympathetic
Horner SyndromeEfferent Defect, Sympathetic

8. Afferent Pupillary Defect
Partial lesion in the afferent pathway;
Optic nerve, chiasm, tract
• Pupil does not respond to light directly
• Pupil respond to light consensually
• Pupils are equal in size (No anisocoria)
• Near reflex is normal

10. III nerve palsy
Occulomotor palsy; traumatic, (common pupil involvement) stroke (less common pupil involvement)
• Ptosis (sever)
• Outward ocular deviation
• Mydriasis (anisocoria, more in bright light)
Efferent Defect, Parasympathetic

11. Ipsilateral Pupil initially constricts (Irritation)
Then dilates due to III nerve compression
As the coma deepens,
contralateral pupil dilates

12. Horner Syndrome
Destruction of sympathetic supply of the iris, e.g. neck surgery, Pancost tumour
• Ptosis (Mild)
• Miosis (anisocoria, more in dim light)
• Anhydrosis (Hemifacial)
Efferent Defect, Sympathetic
• Enophthalmos
• Heterochromia iridis (Congenital Horner)

13. Ciliospinal Reflex:
dilation of the
ipsilateral pupil in
response to pain
applied to the neck.

16. Light Near Dissociation (LND)
• Bilateral
• Small irregular pupil
• Pupil does not react to light
• Pupil constrict during near reflex
• Neurosyphilis
• Diabetes
• Encephalitis
Lesion in Intercalated neurons in the Peri
aqueductal area
Fibres subserving light reflex are more ventral

18. Light Near Dissociation (LND)
• Commonly unilateral
• Large irregular pupil
• Poor response to light
• Slow & tonic response to near reflex
• Late lesions, the pupil becomes miotic (Little old Adie’s)
• Associated absent deep tendon reflexes (Holmes-Adie syndrome)
• Viral
Lesion in the Ciliary Ganglion

21. Unequal Pupil Size

22. Check light reflex
CocaineED

23. Miosis Mydriasis
Physiological
• Light reflex
• Near reflex
• Senile
• Sleep
• 3rd stage of anaesthesia
• Dim Illumination
• Fear, Fight, Fright
• 1st, 2nd & 4th stages of anaesthesia
• Cilio-spinal rflex
Drugs
• Parasympathomimetics: Pilocarpine
• Morphine
• Opium
• Sympathomimetics: Epinephrine
• Parasympatholytics: Atropine,
Cyclopentolate
Neurological
• Argyll Robertson
• Horner
• Hutchinson (Irritative stage)
• Little old Adie’s
• Pontine haemorrhage
• III nerve palsy
• Adie’s tonic pupil
• Hutchinson (Paralytic stage)
Ocular
• Keratitis
• Iritis
• Trauma
• Acute congestive glaucoma
• Trauma

24. • Nucleus
• Nerve
• Muscle
1. Congenital
2. Trauma
3. Inflammation
4. Vascular
5. Tumor
6. Metabolic
7. Toxic
LMNL

25. • Diplopia: that increases toward the side of the paralysed muscle
• Ocular deviation
• Abnormal Head Posture

30. • Contracture
• Contracture
• Underaction
(inhibitional palsy)

31. False projection (Hess screen)

32. • Inward
• Abduction
• Increases on looking outwards
• Face turn toward the
paralysed muscle

33. • Upward
• Down & in
• Increases on looking down & in
• Head tilt to the
opposite shoulder
• Chin depression
• Face turn to the same
side

34. Parks’ (Bielschowsky) 3 step test
• Right eye hypertropic
• Elevation increases
to the left gaze
• Elevation decreases
in the left head tilt

35. • Outward
• In all directions except outward

36. • Treat the cause, if possible e.g. brain tumour, trauma, …
• Temporary measures; (in the 1st 6 months of the insult)
A. Occlusion of the sound eye
B. Relieving prisms
• Surgical treatment;
6th nerve palsy >>> MR recession +/- vertical muscle transposition
4th nerve palsy >>> IO myectomy
3rd nerve palsy >>> LR recession then treat ptosis

37. Visual
System
1) Optic nerve
2) Optic Chiasm: where nasal fibres
cross to the opposite side
3) Optic Tract: carrying ipsilateral
temporal fibres & contralateral nasal
fibres
4) Lateral Geniculate Body
5) Optic Radiation: The upper
radiation (Parietal lobe) subserve the
lower visual field, while the lower
radiation (Temporal lobe) subserve the
upper visual field
6) Visual Cortex

38. Visual
System
Optic Nerve Function Tests
1) VA
2) Pupil reactivity
3) Colour vision
4) Visual field
5) VEP

39. ONH Swelling
Normal Optic Nerve Functions
Crowded, High hypermetropia Tilted
Affected
Optic Nerve
Functions
1) Inflammatory
2) Ischemic
3) Compressive
4) Increased ICT
5) Toxic
6) Vascular; CRVO

40. Swelling of the optic nerve head secondary to raised intracranial pressure (ICP).
A. Idiopathic Intracranial Hypertension (IIH); the commonest cause
B. Space occupying lesion e.g. tumour
C. Obstruction of the ventricular system
D. Cerebral venous sinus thrombosis
E. Cerebral edema e.g. head trauma

41. • Raised ICP is transmitted via subarachnoid space acting as a tourniquet around the
optic nerve
• This causes disturbance of the axoplasmic flow along retinal nerve fibres resulting
in stasis swelling of these axons & leakage

42. 1. Headache: more in early morning and may awake the patient from sleep
2. Nausea
3. Vomiting: projectile (sudden & forceful)
4. Deterioration of consciousness
1. Transient visual obscuration (Amaurosis Fugax) : precipitated by bending, cough or
Valsalva manoeuvre
2. Horizontal diplopia: 6th nerve palsy
3. Visual Acuity: Normal in early stages, but shows significant reduction later on
• IIH occurs in obese young adult women.
• Various medications have been implicated especially the Oral Contraceptive Pills

43. • Limited abduction with inward ocular deviation
• 6th nerve palsy may occur due to stretching of one
or more of the abducens nerve over the petrous
tip.
• It is considered as a false localising sign

44. • Mild optic disc hyperaemia with
preservation of optic cup
• Indistinct disc margins
• Disappearance of the previously present
spontaneous venous pulsations

45. • VA is normal or mildly affected
• Severe optic disc hyperaemia with absent
optic cup
• Moderate optic disc elevation
• Indistinct disc margins
• Venous engorgement
• Peripapillary flame shaped haemorrhage &
CWS
• Circumferential retinal folds (Paton lines)
• Enlarged blind spot

46. • VA is reduced
• Constricted visual field
• Disappearance of haemorrhage & cotton
wool spots

47. • VA is severely impaired
• Optic disc is pale grey white with few
crossing blood vessels and indistinct
margins

49. • Papilledema is a bilateral condition
• Except in rare instances as (Foster Kennedy Syndrome)
• Left Olfactory groove tumour causing left optic
atrophy & right papilledema
R

51. • To measure the Optic Nerve Sheath External Diameter (ONSD) Which is substantially
distended

52. • To exclude space occupying lesions &/or
enlarged ventricles
• Used also to measure the ONSD
• To measure CSF opening pressure (Normal 10 - 18 cm water) and also to analyse
CSF constituents
• Must not be done except after neuro imaging to avoid herniation of intracranial contents
in case of space occupying lesion

53. 1. Transient ischemic attacks
2. Retinal migraine
3. Hysterical
4. Malingerer
1. Pseudo: Drusen, Hyperopia,Tilted disc
2. True:
A. Ischemic
B. Inflammatory
C. Vascular

54. • Mainly directed to the cause
1. Weight loss
2. Acetazolamide, Frusemide
3. IV mannitol
4. Lumbar puncture
5. Optic nerve sheath fenestration
(in unresponsive cases)
6. Ventriculo peritoneal shunt
surgery

55. Occlusion of the blood supply (SHORT
CILIARY VESSELS) of the optic nerve,
either;
• Anterior (AION): 90% of cases, or
• Posterior (PION)

56. 1. AION:
A. Non Arteritic (NAION): DM & HTN are the commonest causes
B. Arteritic (AAION): caused by Giant cell arteritis (GCA)
2. PION:
• Caused by ischemia of the retro laminar portion of the optic nerve head especially post
bloody surgeries. It might be also caused by arteritic or non arteritic causes.

57. 1. NAION: Old age, history of DM, HTN
2. AAION: Old age, Scalp tenderness (with combing hair), headache, jaw claudication
3. PION: History of bloody surgery
1. Sudden loss of vision:
• Painless: NAION
• Painful: AAION

58. SUPERFICIAL TEMPORAL
ARTERY:
• Tender
• Loss of pulsations
• Thickened
• Nodular

59. • VA: severely reduced (more in AAION)
• Pupil: RAPD
• Ocular nerve palsies: in AAION

60. ONH:
• Swollen
• Pale
• Splinter haemorrahge at ONH
margin
• might be associated with
cilioretinal artery occlusion

61. ONH:
• Swollen (Diffuse or Sectoral)
• Hyperaemic
• Splinter haemorrahge at ONH
margin (Few)
• might be associated with diabetic
or hypertensive retinopathies

62. • Temporal Artery Biopsy (TAB)
• ESR
• CRP
• HbA1c
• Blood pressure monitoring

63. • Altitudinal field defect

64. 1. Pseudo: Drusen, Hyperopia,Tilted disc
2. True:
A. Elevated ICP
B. Inflammatory
C. Vascular
1. CRAO
2. CRVO
3. RD
4. Malingerer

65. • Intravenous methyl prednisolone 1g/day for 3 days followed by oral prednisolone
• Anti platelet therapy e.g. Aspirin to reduce risk of stroke
• Immunosuppressives e.g. Methotrexate
• Aim: to prevent blindness of the fellow eye
• NO DEFINITE treatment
• Anti platelet therapy e.g. Aspirin to reduce risk of stroke
• Strict control of DM & HTN

66. • Tortuosity & engorgement of
all branches of CRV
• Blot & flame shaped retinal
haemorrhage
• Cotton wool spots
• ONH swelling & hyperaemia
• Macular edema

67. • Papillitis: Inflammation of the ONH
• Retro Bulbar neuritis: inflammation of the retro laminar part of the optic nerve
A. Demeylinating: most common
B. Infectious: Herpes zoster,
Syphilis
C. Para infectious: following viral
infection or immunisation
D. Non infectious: Sarcoidosis,
Auto immune disease

68. • Idiopathic demyelinating disease involving the white mater of the central nervous system
Demyelination is a pathological process in
which normally myelinated nerve fibres lose
their insulating myelin layer. The myelin is
phagocytosed by microglia and macrophages,
subsequent to which astrocytes lay down
fibrous tissue in plaques. Demyelinating
disease disrupts nervous conduction within
the white matter tracts of the brain, brainstem
and spinal cord.

70. 1. Spinal cord: weakness, sensory loss, sphincter disturbance
2. Brainstem: Diplopia, Nystagmus, Dysphagia
3. Cerebral: Hemiparesis, Hemianopia
1. Optic neuritis
2. Ocular motor nerve palsies
3. Intermediate uveitis

71. • Demyelinating Optic neuritis
Young age
Discomfort or pain around
the eye especially on
looking on the field of MR,
SR
VA deteriorates rapidly
within several days to 3
weeks, then begin to
improve
RAPD
Optic disc might appear
normal (Retrobulbar
neuritis), or Swollen
(Papillitis)

72. Peri ventricular plaques

73. A. Central scotoma
B. Centro cecal scotoma
C. Nerve fibre bundle defect
D. Altitudinal field defect

74. • Intravenous methyl prednisolone 1g/day for 3
days followed by oral prednisolone
• Beta interferone
Treatment may speed up recovery by 2–3 weeks and may delay the onset of clinical
MS over the short term. This may be relevant in the patients with poor vision in the
fellow eye or those with occupational requirements, but the limited benefit must be
balanced against the risks of high-dose steroids.
Therapy does not influence the eventual visual outcome and the great majority of
patients do not require treatment.

75. A. High Alcohol (Ethyl Alcohol), Tobacco consumption
B. Poor diet, deficient in vitamin B complex
particularly, Cyanocobalamin (B12), Thiamine (B2),
Niacin (B3) & Pyridoxine (B6)
C. Strict vegan diet with deficient protein & iron
especially in elderly

76. • Deficient mitochondrial function especially in the papillo macular bundle (Cyanide
toxicity)
• Bilateral painless central blurring of vision with insidious onset
• Peripheral neurological symptoms e.g. sensory loss, gait disturbance
• History of exposure to the risk factors
• VA: Variable
• Colour vision: central scotoma to red
• ONH: minimal edema, subtle pallor
• Visual field: Bilateral centro cecal scotoma

77. Bilateral
centro
cecal
scotoma

78. • Abstention of Tobacco & Alcohol
• IM B12 1gm weekly for several weeks
• Daily multi vitamin preparation plus folate
• In someone who is both folate and
B12 deficient, it is prudent to
correct the B12 deficiency first to
avoid precipitating subacute
combined degeneration of the
cord.

79. • Quinine is an anti malarial
• Idiosyncrasy to the drug leads to near total blindness, deafness & tinnitus
• Fundus exam shows retinal edema, marked attenuation of retinal vessels & pallor of the
ONH
• Oxidised into formic acid & formaldehyde which are toxic to ganglion cells
• Clinical features: Headache, dizziness, nausea, vomiting, abdominal pain, delirium and
even death with characteristic formaldehyde odour
• Ocular features: ONH edema with marked attenuation of retinal vessels followed by
optic atrophy
• Treatment: Gastric lavage, Sodium bicarb (oral or IV), Ethyl Alcohol, Peritonial dialysis

80. ONH Swelling
• True vs Pseudo
• Unilateral vs Bilateral
• Young vs Old age

81. • Death of the retinal ganglion cell axons that comprise the optic nerve with the resulting
picture of a pale optic nerve on funduscopy.
• Optic atrophy is an end stage that arises from myriad causes of optic nerve damage
anywhere along the path from the retina to the lateral geniculate body.
• due to causes outside the eye ball
• due to Optic disc diseases
• due to Chorio retinal diseases
• 2ry to Glaucoma

82. Optic Nerve Functions
1) VA: diminished
2) Pupil reactivity: RAPD
3) Colour vision: Reuced
4) Visual field: Scotoma
5) VEP: decrease
amplitude,increased latency

83. • Leber hereditary optic neuropathy
• MS • Neurosyphilis
• Pituitary • ON sheath meningioma
• Colour: Milky White
• Edges: Well defined
• Cup: Shallow
• Lamina: well seen
• Retinal vessels: Normal or slightly attenuated
• Rest of the fundus: Normal

84. • Optic neuritis
• Papilledema
• Colour: Dirty Greyish White
• Edges: Ill defined
• Cup: Obliterated
• Lamina: Not seen
• Retinal vessels: Attenuated +/- sheathing
• Rest of the fundus: Normal

85. • Tay Sachs disease
• Colour: Waxy yellow
• Edges: Slightly Ill defined
• Cup: Normal
• Lamina: Not seen
• Retinal vessels: Markedly Attenuated
• Rest of the fundus: Causative lesion

86. • Colour: Pale
• Edges: Over hanging
• Cup: Deep, Large
• Lamina: Well seen
• Retinal vessels: Bayoneting
• Rest of the fundus: Peri papillary
changes

88. Neurological Visual Field Defects
• Total Optic nerve destruction
leads to total visual field loss

89. Neurological Visual Field Defects
• Central Scotoma
DDx
1. Optic neuritis
2. Toxic amblyopia
3. Macular lesion

90. Neurological Visual Field Defects
• Centrocecal Scotoma
DDx
1. Optic neuritis
2. Toxic amblyopia

91. Neurological Visual Field Defects
• Altitudinal visual field defect
DDx
1. Optic neuritis
2. AION
3. BRAO
4. BRVO
5. Sectoral RP

92. Neurological Visual Field Defects
• Bundle visual field defect
(Glaucoma, optic neuritis)

93. Neurological Visual Field Defects
• Bitemporal hemianopia, due
to affection of the
decussating nasal fibres on
both sides

94. Neurological Visual Field Defects
• Contralateral Homonymous
Hemianopia, due to affection
of ipsilateral temporal fibres
& contralateral nasal fibres

95. Neurological Visual Field Defects
• Contralateral Homonymous
Upper Quadrantopia, (Pie in
the sky)

96. Neurological Visual Field Defects
• Contralateral Homonymous
Lower Quadrantopia, (Pie on
the floor)

97. Neurological Visual Field Defects
• Contralateral Homonymous
Hemianopia with macular
sparing, WHY?!
(Macula is supplied by the Middle
cerebral artery while the rest of
the visual cortex is supplied by
posterior cerebral artery. Macula
has wide cortical representation
so any incomplete cortical lesion
cannot affect the macula)

98. Neurological Visual Field Defects
• Contralateral Homonymous
macular defect.

99. Visualpathways
correlationoflesionsiteandfielddefect

100. Where is the lesion?
R L

101. Where is the lesion?

102. Where is the lesion?

103. Where is the lesion?
R L