Neuro-ophthalmology for Medical Student Surat Tanprawate, MD, MSc(London), FRCP(T) Neurology Unit, Department of Medicine Chiang Mai University
Wednesday, October 31, 2012
The scope of Neuro-ophthalmology •
Oculomotor system
•
conjugate eye movement
•
Saccadic system
•
Pursuit system
•
Vergence system
•
Counter rolling system: VOR, Ocular fixation system
Wednesday, October 31, 2012
•
Visual perception system
• •
Eyelids Pupils
The scope of Neuro-ophthalmology •
Oculomotor system
Disconjugate eyes: diplopia
•
conjugate eye movement
•
Saccadic system
•
Pursuit system
•
Vergence system
•
Counter rolling system: VOR, Ocular fixation system
Wednesday, October 31, 2012
•
Visual perception system
• •
Eyelids Pupils
The scope of Neuro-ophthalmology •
Oculomotor system
Disconjugate eyes: diplopia
•
conjugate eye movement
•
Saccadic system
•
Pursuit system
•
Vergence system
•
Counter rolling system: VOR, Ocular fixation system
Wednesday, October 31, 2012
•
Visual perception system Visual loss
• •
Eyelids Pupils
The scope of Neuro-ophthalmology •
Oculomotor system
Disconjugate eyes: diplopia
•
conjugate eye movement
•
Saccadic system
•
Pursuit system
•
Vergence system
•
Counter rolling system: VOR, Ocular fixation system
Wednesday, October 31, 2012
•
Visual perception system Visual loss
• •
Eyelids Pupils
Ptosis
The scope of Neuro-ophthalmology •
Oculomotor system
Disconjugate eyes: diplopia
•
conjugate eye movement
•
Saccadic system
•
Pursuit system
•
Vergence system
•
Counter rolling system: VOR, Ocular fixation system
Wednesday, October 31, 2012
•
Visual perception system Visual loss
• •
Eyelids Pupils
Ptosis Anisocoria
Oculomotor pathway • Supranuclear(UMN) • FEF: horizontal conjugate gaze • Diffuse frontal and occipital: vertical conjugate gaze
• Nuclear (LMN) • CN III, IV, VI • Internuclear • PPRF, abducen interneuron, MLF (Horizontal gaze) • riMLF, INC, PC (Vertical gaze)
• Infranuclear(LMN) • • • •
Faciculus Cranial nerve NMJ muscle
Wednesday, October 31, 2012
Frontal eye fields
Wednesday, October 31, 2012
Right frontal lobe infarct
Frontal lobe lesion: no diplopia - Destructive FEF lesion:
• eyes deviate to the lesion - Excitatory lesion:
• eyes deviate to contralateral to the lesion Wednesday, October 31, 2012
Diplopia (double vision)
pic from wikipedia
Wednesday, October 31, 2012
•
Diplopia is the simultaneous perception of the two images of a single object that may be displaced horizontally, vertically, diagonally
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caused by impair EOMs functions
Diplopia Monocular diplopia
Repetitive images
- Cerebral polyopia - Non-organic
Binocular diplopia
Ghosting image
- Retinal disease - Refractive error
Misalignment of the eyes
Nuclear control
- CN III - CN IV - CN VI
Wednesday, October 31, 2012
Infranuclear control
- CN palsy - NMJ disorder - Muscle disorder
Internuclear control
Horizontal diplopia - INO - PPRF Vertical diplopia - INC, riMLF
Key features •
Nuclear and fascicular lesion
• •
Brain stem sign: long tract sign, other CN involvement
Nerve lesion
• •
Neighborhood sign; other CN, other sign
Internuclear lesion
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specific syndrome; Internuclear Ophthalmoplegia (INO), WEBINO, One and a half syndrome
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NMJ lesion: fatiguability, not consistent with CN lesion, sign of myasthenia gravis
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Muscle lesion: not consistent with CN lesion: not consistent with CN lesion, sign of myopathy
Wednesday, October 31, 2012
The action and nerve supply of the extraocular muscles is demonstrated.
Wednesday, October 31, 2012
Nuclear and nerve lesion
Wednesday, October 31, 2012
CN III
The oculomotor nerve (cranial nerve III)
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CN IV
The course of the trochlear nerve in the pons
Wednesday, October 31, 2012
CN VI
facial nerve wraps around the nucleus of cranial nerve VI within the pons
Wednesday, October 31, 2012
A woman with acute diplopia for 2 weeks
Wednesday, October 31, 2012
A woman with acute diplopia for 2 weeks
Right LR palsy; No other neurological sign, MRI brain-normal
Wednesday, October 31, 2012
A woman with acute diplopia for 2 weeks
Right LR palsy; No other neurological sign, MRI brain-normal
“Pure Right CN VI palsy” Wednesday, October 31, 2012
A 55 Y.O. with DM, HT presented with acute diplopia for 2 days
Wednesday, October 31, 2012
A 55 Y.O. with DM, HT presented with acute diplopia for 2 days
Left LR palsy Wednesday, October 31, 2012
A 55 Y.O. with DM, HT presented with acute diplopia for 2 days
Left LR palsy Dx. “Left CN VI palsy from ischemic neuropathy” Wednesday, October 31, 2012
Bilateral LR could be pseudo sixth nerve palsy from IICP
Wednesday, October 31, 2012
Third nerve palsy
Wednesday, October 31, 2012
Multiple oculomotor nerve involvement
• Cavernous sinus syndrome • Superior orbital fissure syndrome
Wednesday, October 31, 2012
Cavernous sinus syndrome • Association with – other cranial nerve involvement: 4, 5, 6 CN – oculosympathetic paralysis – Opthalmic branch of trigeminal nerve
• Tend to be partial; alls muscles innervated are not equally involved
19 Wednesday, October 31, 2012
Superior orbital fissure syndrome
CN 3, 4, 6, V1 20 Wednesday, October 31, 2012
Superior orbital fissure syndrome • Involve CN 3, 4, 6 and V1 CN 5 distribution +/oculosympathetic paresis without anhydrosis • May exopthalmos due to blockade of the opthalmic veins • Blindness due to extension of the pathologic process to involve the optic canal
21 Wednesday, October 31, 2012
A patient with diplopia for 1 week with gait ataxia and areflexia
2 weeks
Wednesday, October 31, 2012
2 months
A patient with diplopia for 1 week with gait ataxia and areflexia
2 weeks
2 months
in a patient with polyneuropathy, all CN can be involved causing total ophthalmoplegia Wednesday, October 31, 2012
A patient with diplopia for 1 week with gait ataxia and areflexia
2 weeks
2 months
Dx. Miller Fisher syndrome in a patient with polyneuropathy, all CN can be involved causing total ophthalmoplegia Wednesday, October 31, 2012
Interneuclear lesion Interneuclear ophthalmoplegia (INO): MLF lesion Bilateral INO : Bilateral MLF lesion One and a half syndrome: PPRF lesion + MLF lesion
Wednesday, October 31, 2012
Unilateral MLF lesion • “ internuclear ophthalmoplegia “ • Ipsilat. MR weakness • Ipsilat. abducting saccade • Contralat. adducting nystagmus • Dissociated nystagmus
Wednesday, October 31, 2012
Interneuclear ophthalmoplegia (INO)
a. Normal primary position
c. Normal left abduction on left gaze Wednesday, October 31, 2012
b. Left impaired adduction on right gaze and horizontal nystagmus of the right eye
d. Normal convergence
Bilateral MLF lesion • Bilateral MLF lesion – Bilateral adducting weakness – Bilateral abducting nystagmus – Impaired vertical vestibular and pursuit – Impaired vertical gaze holding – Gaze evoked nystagmus
• Wall eyed bilateral INO : WEBINO – exotropia
Wednesday, October 31, 2012
A man with sudden diplopia
WIBINO Wednesday, October 31, 2012
One and a half syndrome • Combined lesion : PPRF and MLF • “ One and a half syndrome “ – Ipsilateral horizontal gaze palsy – INO
Wednesday, October 31, 2012
Wednesday, October 31, 2012
Infranuclear lesion ; disease of ocular muscle disease of NMJ
Wednesday, October 31, 2012
Total ophthalmopathy in CPEO patient
Wednesday, October 31, 2012
TRIO with Bilateral ptosis (MG)
Wednesday, October 31, 2012
• Upper eyelid – Levator palpebral superioris(CN 3) – Muller muscle (sympathetic) – Frontalis muscle(CN 7)
• Lower eyelid – Capsulopalpebral fascia (inferior rectus) – Inferior tarsal muscle (sympathetic)
Wednesday, October 31, 2012
Ptosis Non-neurogenic(mechanical) ptosis
Neurologic ptosis Congenital ptosis
•Uni-bilateral •Partial-complete
Supranuclear lesion (cerebral ptosis) •Contralateral cerebral hemisphere
Wednesday, October 31, 2012
•Pupil involvement •EOM impairment
LMN •Neuropathic(N, fascicle, CN) •NMJ •Myopathic
Horner’s syndrome
Ptosis from Cranial nerve III lesion - complete or near complete ptosis - EOM involvement - Pupil dilatation
Wednesday, October 31, 2012
MG with enhancing ptosis
Ptosis due to NMJ lesion: sign of fatiguability Wednesday, October 31, 2012
Nystagmus
Wednesday, October 31, 2012
Nystagmus •
Ancient Greek (nustagmos (Ancient Greek, "nodding, be sleepy")
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Involuntary biphasic rhythmic ocular oscillation in which one or both phase are slow
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The slow phase is responsible for the initiation and generation of the nystagmus, whereas the fast (saccadic) phase i a corrective movement bringing the fovea back on target
•
Type: jerk (direction to fast phase) ; pendular nystagmus
Wednesday, October 31, 2012
Mechanism • Nystagmus may result from dysfunction
of the vestibular ending organ, vestibular nerve, brainstem, cerebellum, or cerebral centers for ocular pursuit
Wednesday, October 31, 2012
A schematic illustration of nystagmus waveforms
(A) pendular nystagmus
(B) an accelerating velocity exponential slow phase jerk nystagmus (CN) (C) a decelerating exponential slow phase jerk nystagmus (MLN) (D) a linear or constant velocity slow phase jerk nystagmus (MLN) In (A) a slow phase is followed by a slow phase while in (B)–(D) a slow phase is followed by a fast phase Wednesday, October 31, 2012
Mechanism • •
Pendular nystagmus: is central (brainstem/cerebellum) Jerk nystagmus:
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linear (constant velocity) slow phase: peripheral vestibular dysfunction
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slow phase has decreasing velocity exponential: brainstem neural integrator
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slow phase has increasing velocity exponential: central in origin (usual form of congenital nystagmus)
Wednesday, October 31, 2012
A woman with periodic vertigo occur when changing position
“vestibular nystagmus” Wednesday, October 31, 2012
case study: a boy with subacute dizziness
Wednesday, October 31, 2012
Wednesday, October 31, 2012
Conclusion •
Oculomotor system
•
conjugate eye movement
•
Saccadic system
•
Pursuit system
•
Vergence system
•
Counter rolling system: VOR, Ocular fixation system
Wednesday, October 31, 2012
•
Visual perception system
• •
Eyelids Pupils
Conclusion •
Oculomotor system
Disconjugate eyes: diplopia
•
conjugate eye movement
•
Saccadic system
•
Pursuit system
•
Vergence system
•
Counter rolling system: VOR, Ocular fixation system
Wednesday, October 31, 2012
•
Visual perception system
• •
Eyelids Pupils
Conclusion •
Oculomotor system
Disconjugate eyes: diplopia
•
conjugate eye movement
•
Saccadic system
•
Pursuit system
•
Vergence system
•
Counter rolling system: VOR, Ocular fixation system
Wednesday, October 31, 2012
•
Visual perception system Visual loss
• •
Eyelids Pupils
Conclusion •
Oculomotor system
Disconjugate eyes: diplopia
•
conjugate eye movement
•
Saccadic system
•
Pursuit system
•
Vergence system
•
Counter rolling system: VOR, Ocular fixation system
Wednesday, October 31, 2012
•
Visual perception system Visual loss
• •
Eyelids Pupils
Ptosis
Conclusion •
Oculomotor system
Disconjugate eyes: diplopia
•
conjugate eye movement
•
Saccadic system
•
Pursuit system
•
Vergence system
•
Counter rolling system: VOR, Ocular fixation system
Wednesday, October 31, 2012
•
Visual perception system Visual loss
• •
Eyelids Pupils
Ptosis Anisocoria
Thank you for your kind attention Wednesday, October 31, 2012
The Neurologist CMU
Wednesday, October 31, 2012
