NEURO-OPHTHALMOLOGY
Clinical Examination
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Visual Acuity
Colour Vision
Visual Fields
Pupils
Normal Eye and Optic Disc
Cupped disc
The swollen optic disc
•Papilloedema
•Papillitis
•Malignant hypertension
•Ischaemic optic neuropathy
•Diabetic optic neuropathy
•CRVO
•Intraocular inflammation
25 y.o. female
Reduced VA
Pain with eye movement
Colour desaturation
RAPD
65 y.o. male
Reduced VA
Painless loss of vision
Essential hypertension
Smoker
The pale optic disc
•Congenital
•Secondary to
•raised ICP
•vascular
retinal disease
•optic neuritis
•optic nerve
compression
•trauma
•Glaucoma
Papilloedema
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Disc swelling secondary to raised
ICP
Haemorrhages
Headache
– Worse in the morning
– Valsalva manouver
Nausea and projectile vomiting
Horizontal diplopia (VI palsy)
Causes
Disc pallor
– Space occupying lesion
– Intracranial hypertension
• Idiopathic
• Drugs
• Endocrine
Vessel attenuation
– Severe hypertension
Blurred optic
disc margin
CWS
Small optic
cup
Pupils
• First Order – Retina to Pretectal Nucleus in B/S
(at level of Superior colliculus)
• Second Order – Pretectal nucleus to E/W nucleus
(bilateral innervation!)
• Third Order – E/W nucleus to Ciliary Ganglion
• Fourth Order – Ciliary Ganglion to Sphincter
pupillae (via short ciliary nerves)
Pupil
• Constricted (mioisis)
– Sympathetic
(pupillodilator)
denervation
– Drugs
• Pilocarpine
• Morphine
• Dilated (mydriasis)
– Parasympathetic
(pupilloconstrictor)
denervation
– Lesion of the third CN
– Drugs
• Atropine
• Cocaine
Horner’s
• Oculosympathetic
paresis
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Ptosis
Miosis
Ipsilateral anhidrosis
Does not dilate with
cocaine 4%
Sympathetic Pathway
• First Order – Posterior Hypothalamus to
Ciliospinal centre of Budge (C8-T2)
(Uncrossed in Brainstem)
• Second Order – Ciliospinal centre of Budge to
Superior Cervical Ganaglion
• Third Order – Superior Cervical Ganglion to
dilator pupillae muscle. (Close to
ICA and joins V1 intracranially)
Internal Carotid Dissection
Herpes
Zoster
Otitis Media
Tolosa-Hunt Sy.
CVA
Tumour
Pancoast bronchogenic carcinoma
Causes of Horner’s pupil
• Central – B/S lesions (tumours, vascular and MS)
Syringomyelia, Lat. Med. Syn., S.C. ca.
• Preganglionic – Pancoast tumour, Carotid & Aortic
aneurysms, Neck lesions/trauma.
• Postganglionic – Cluster headaches, Nasopharyngeal
tumours, Otitis media, Cavernous
sinus mass and ICA disease.
• Miscellaneous – Congenital (brachial plexus injury)
Idiopathic.
Afferent & efferent defects
• Argyll-Robertson
pupil
– Small, irreg
– Does not react to light
– Reacts to
accommodation
– Causes
• syphilis
• diabetes
• Miotonic pupil (Adie’s
syndrome)
– Dilated
– Poor response to light and
convergence.
• Constricts with weak
Pilocarpine
• Holmes-Adie syndrome
– Reduced tendon reflexes
(Knee, ankle)
- Orthostatic hypotension
Ocular motility abnormalities
• Third nerve palsy
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Double vision
Eye turned down & out
Ptosis
Dilated pupil &
headache
• Compressive lesion
• Sixth nerve palsy
– Double vision
– Eye turned in
Cranial Nerve Palsies
Looking straight ahead
Posterior communicating artery aneurysm
Chiasma
Posterior cerebral
artery
III CN
Internuclear Ophthalmoplegia
• Defective adduction of the
ipsilateral eye
• Nystagmus of the contralateral
(abducting) eye
• NORMAL CONVERGENCE
• Causes
– Young patients
• Bilateral
• Demyelination
– Older patients
• Unilateral
• Vascular, tumours
Myasthenia Gravis
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Fatigability
Double vision
Lid twitch
Ptosis
Normal reflexes &
sensation
INVESTIGATIONS MG
ACh
Anti AChR Ab’s
AChR
• Anti ACh receptor Ab’s
• Electromyography
• Tensilon test
– Edrophonium blocks
acetyl-cholinesterase
– Beware of cholinergic
cardiac effects. Use
with Atropine 0.6mg
• Thoracic CT and MRI to
rule out thymoma
Localising the lesion
• Monocular visual field defects indicate
lesions anterior to the optic chiasm
• Bitemporal defects are the hallmark of
chiasmal lesions
• Binocular homonymous hemianopia result
from lesions in the contralateral
postchiasmal region
• Binocular quadrantanopias reflect optic
tract lesions