EYES IN FINALS
• SHORTS
• TAGGED ON TO NEURO EXAM
• TINY PROPORTION OF THE MARKS
• Can make you look really clever
• RELAX
Neuro-ophthalmology for finals
Tom Marjot
To do…
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Pupillary abnormalities
Horners syndrome
Eye movements and Ophthalmoplegia
Visual field defects
Special cases
– Multiple Sclerosis
– Myasthenia gravis
– Cerebellar disease
Pupillary abnormalities
Relative Afferent Pupillary Defect
Rehearse! – come up with your own script
“Stimulation of the normal eye produces full constriction of
both pupils – both direct and consensal reflexes are intact”
“Subsequent stimulation of the affected eye causes
dilatation of both the pupils”
“This is because the consensual pathway from the normal
eye (which is now in darkness) is stronger than the afferent
pathway from the pathological eye”
Relative Afferent Pupillary Defect
…“These findings are consistent with a RAPD…otherwise
known as a Marcus Gunn Pupil”
REMEMBER:
If you pick up a pen-torch in finals it is synonymous with “I am looking
for a RAPD”
Difference in pupil size in all other pathologies (Horners, oculomotor
palsy, brainstem herniation) will NOT require a pen torch.
….. When I shine a light in the eye does the pupil dilate?
“What are the causes of RAPD?......”
“Disorders of the optic nerve
Or Disorders of the Retina
… I would therefore like to perform fundoscopy
Optic nerve:
Optic neuritis/atrophy – Multiple Sclerosis
Retina:
Retinal detachment, retinal vein or artery occlusion,
severe diabetic retinopathy
“RAPD there must be a difference in the extent of the disease
between the two eyes”
RAPD
• Have a script
• Pen-torch = RAPD = does pupil dilate
when I shine a light?
• Afferent pathway involves - nerve or
retinal
• Offer fundoscopy
Unequal pupils
A starting point:
• Don’t need a pen-torch
• Look carefully
• Smaller = ‘miotic’ Larger = ‘mydriatic’
• Unequal = “Anisocoria”
“The patient has marked anisocoria with a left miotic pupil”
“The is also a visible (partial) left sided …………..Ptosis”
“This gives the impression of apparent enophthalmos”
“These findings would be consistent with a left Horners
Syndrome”
So you’ve landed at Horner's Syndrome (Correctly)
Now sit and wait for the questions or you can be proactive.
Remember your differentials
- You have discovered and commented on a ptosis
- State that you would like to check for ophthalmoplegia (eye movements)
because Myasthenia gravis and Oculomotor nerve pasy also give a ptosis.
No opthalmoplegia and given the clearly miotic left pupil – Horner’s Syndrome.
Silly because impossible to accurately clinically determine but
important for exams ………
Pattern of ANHIDROSIS
ANHIDROSIS
1
3
More peripheral the lesion the
less sweating is affected
2
1 - Face, arm and trunk
2 – Face
3 – Not affected
Unilateral ptosis
1. Horners syndrome
2. III nerve Palsy
3. Myasthenia Gravis
Bilateral ptosis
1. Myasthenia Gravis
1
3
Central or Peripheral lesions  Horner’s
Central
Demyelination
Tumour
2
Peripheral
Pancoast tumour
Cervical rib
Neck/cardiothoracic surgery
Heterochromia
Associated with congenital Horners
Horner’s Syndrome
• Ptosis + miosis
• Remember ptosis differentials and check
eye movements
• Causes can be central or peripheral
“The patient has a complete left sided
ptosis”
“There is also marked aniscocoria with a
mydriatic pupil on the left”
“There is a left divergent stabismus at
rest…. With the eye fixed in a down and
out position”
“These findings would be consistent with
a left III cranial nerve lesion”
• Levator Palpebrae Superioris – CNIII
• Mullers Muscle - Sympathetic
“Due to pupillary involvment this could be
said to be a ‘surgical’ III nerve palsy”
Superior
Oblique - IV
Lateral Rectus VI
Unilateral ptosis
1. Horners syndrome
2. III nerve Palsy
3. Myasthenia Gravis
Surgical
External compressive lesion impinging on parasympathetic fibres
which run very superficially in the nerve trunk
-
Tumour
Haemorrhage
Aneurysm – (Posterior Communicating Artery Aneursym)
Anatomically
Brainstem: Tumour, infarct haemorrhage, demyelination
Cavernous sinus lesion: Tumour, thrombosis
Superior orbital fissure: Trauma
Medical
-
Diabetes
Oculomotor Nerve Palsy
• Ptosis +/- mydriasis
• Divergent strabismus at rest
• Opthalmoplegia
• Medical vs Surgical may help you list
causes
Cavernous Sinus
A large channel of venous blood creating a cavity bordered by the sphenoid bone
and the temporal bone of the skull
Get out of jail card when pushed for causes of Cranial nerve lesions
Tumours, thrombosis,
aneurysms, infections
Oculomotor (III)
Trochlea (IV)
Ophthalmic nerve (V1)
Maxillary nerve (V2)
Abducens (VI)
Internal carotid artery
carrying sympathetic
plexus
Horner’s
IV and VI Nerve
Superior Oblique - IV
Lateral Rectus - VI
Don’t effect pupil
Don’t effect eyelid
VI Nerve Palsy
“The patient has a convergent strabismus
on the right at rest”
Failure to Abduct the eye
“Pupils are equal, no ptosis”
Superior Oblique - IV
Lateral Rectus - VI
Abducens only job
VI (Abducens) Nerve Palsy
?
Right convergent strabismus.
“There is diplopia maximal on right
lateral gaze ” (towards the affected
side)
(because you are trying to move the
eye outwards with a non-functioning
lateral rectus muscle)
Outmost image comes from the
affected eye
Covering the right eye removes the
outer most image
VI Nerve Palsy
• Only innervates Lateral Rectus so can
move eye outwards
• Convergent strabismus at rest
• Diplopia towards affected side
• Outermost image comes from affected
eye
IV Nerve Palsy
• RARE and Unlikely for finals
Trauma is most common
Superior oblique – IN and DOWN
Therefore in a palsy eye
appears higher.
IV Nerve Palsy
• RARE and Unlikely for finals
Trauma is most common
Superior oblique – IN and DOWN
Therefore in a palsy eye
appears higher.
IV Nerve Palsy
• Rare. Trauma.
• Eye higher
• Head tilt to opposite side.
MONONEURITIS MULTIPLEX
• Get out of jail card for nerve lesions
• Simultaneous or sequential involvement of individual non-contiguous
nerves
WARDS PLC
Wegeners
AIDS/Amyloid
Rheumatoid
Diabetes
Sarcoid
Polyarteritis nodosa
Leprosy
Cancer
1. Diabetes
2. Vasculitis
3. Rheumatoid
IIIrd nerve palsy
“What are the causes?”
Surgical:
Tumour
Aneurysm
Haemorrhage
Medical:
Diabetes
…Mononeuritis multiplex
MONONEURITIS MULTIPLEX
• Get out of jail card for nerve lesions
• Simultaneous or sequential involvement of individual non-contiguous
nerves
WARDS PLC
Wegeners
AIDS/Amyloid
Rheumatoid
Diabetes
Sarcoid
Polyarteritis nodosa
Leprosy
Cancer
1. Diabetes
2. Vasculitis
3. Rheumatoid
Foot drop….
“What are the causes?”
“Common peroneal nerve lesion (L5/S1)”
External compression (cast)
Trauma (head of fibula)
Motor Neurone disease
Charcot Marie Tooth
…Mononeuritis multiplex”
VISUAL FIELDS
Age related macular
degeneration
Retinitis pigmentosa
Migraine
Arcuate scotoma
Glaucoma
Bitemporal Hemianopia
• Common for finals
• Easy to detect
“Represent a lesion at the optic chiasm”
• Pituitary tumour
↓TSH
↓T4
Bitemporal Hemianopia
• Common for finals
• Easy to detect
“Represent a lesion at the optic chiasm”
• Pituitary tumour
• Craniopharyngioma
• Menigioma/Glioma
Pituitary tumour
Craniopharyngioma
From Hemiparesis to Homoymous Hemianopia
One of the most likely Neuro cases
Start with PRONATOR DRIFT
Be patient
Ask if Right or Left Handed
Diagnosed Hemiparesis
1. Stroke
2. MS
3. Tumour
Diagnosed Hemiparesis
1. Stroke
2. MS
3. Tumour
BAMFORD Classification of Stroke
1. Hemiparesis
2. Hemianopia
3. Loss Higher functioning
x3 = TOTAL ANTERIOR CEREBRAL INFARCT
X2 = PARTIAL ANTERIOR CEREBRAL INFARCT
Dead @ 1 Year
60%
16%
PICK UP A PEN TORCH
“Im looking for an RAPD”
Hemiparesis + RAPD ………………………………….. MULTIPLE SCLEROSIS
“What are the causes RAPD?......”
“Disorders of the optic nerve
Or Disorders of the Retina
… I would therefore like to perform fundoscopy
Optic nerve:
Optic neuritis/atrophy – Multiple Sclerosis
Retina:
Retinal detachment, retinal vein or artery occlusion,
severe diabetic retinopathy
“RAPD there must be a difference in the extent of the disease
between the two eyes”
SPECIAL CASES
MULTIPLE SCLEROSIS
Multiple Sclerosis, Multiple Eye Signs
• RAPD – optic neuritis/atrophy
• Ophthalmoplegia – any individual muscle or
combination
• Nystagmus (cerebellar involvement)
• Internuclear opthalmoplegia (INO)
Internuclear Ophthalmoplegia
• III
Medial Longitudinal Fasciculus
VI
Medial Longitudinal Fasciculus
• VI
III
Internuclear Ophthalmoplegia
• III
Medial Longitudinal Fasciculus
VI
Medial Longitudinal Fasciculus
• VI
III
Right sided INO
Bad eye fails to
ADduct
Nystagmus
Internuclear Ophthalmoplegia
• III
Medial Longitudinal Fasciculus
VI
Medial Longitudinal Fasciculus
• VI
III
Bilateral INO
Failure to ADduct in both eyes with
contralateral nystagmus
= MS
SPECIAL CASES
Myasthenia Gravis
Unilateral ptosis
1. Horners syndrome
2. III nerve Palsy
3. Myasthenia Gravis
Bilateral ptosis
1. Myasthenia Gravis
Ptosis
Accentuated by upgaze
Opthalmoplegia
Variable and complex
“Intra-saccadic fatigue”
Pupils not involved
15% pure ocular Myasthenia Gravis (more likely to be seronegative)
85% generalized Myasthenia Gravis
Cerebellar eye signs
1 - HORIZONTAL NYSTAGMUS
FAST (saccade)
Towards side of lesion
2 - BROKEN PERSUIT
3 - ABNORMAL SACCADES