Neuro-Opthalmology Flashcards
What are the important causes of optic disc swelling? *
Optic neuritis Papilloedema (must be bilateral) Malignant hypertension Arteritic anterior ischaemic optic neuropathy (arteritic AION) Non-arteritic AION
How does optic neuritis present?
Retrobulbar pain especially with eye movement, associated with globe tenderness
What would be seen on examination of optic neuritis?
disc may not be swollen
relative afferent pupillary defect
red desaturation
central scotoma on field testing
How does papilloedema present?
symptoms include transient visual obscurations
What is seen on examination of papilloedema?
splinter haemorrhages exudates cotton wool spots retinal folds near the disc enlarged blind spots
gradually progressive field loss - generalised constriction
eventual atrophic changes
How does arthritic anterior ischaemic optic neuropathy (AION) present?
temporal headache associated with jaw claudication, weight loss, myalgia
visual loss caused by inflammatory infarction of posterior ciliary artery
ESR and CRP raised
How should arthritic anterior ischaemic optic neuropathy (AION) be treated?
needs urgent treatment with high dose steroids
temporal artery biopsy should be performed within a week of starting treatment
treatment continues for at least 2 years
What would be seen on examination of the eye with AAION?
optic disc margin is blurred and disc is pale
as disc is swollen
What is non-arteritis AION?
Infarction of PCA as for AAION
What are the differences between AAION and NAION?
In NAION
ESR is not raised
50% of patients are hypertensive
No systemic symptoms
What is optic atrophy?
end stage eye disease
associated with APD
What would be seen on eye examination of a patient with optic atrophy?
optic disc is pale compared to a healthy disc
Which muscles are affected in a IIIrd nerve palsy?
medial rectus inferior rectus superior rectus inferior oblique levator palpeerde superioris
How does the eye present in a third nerve palsy?
eye points down and out
ptosis
dilated pupil
no afferent pupillary defect
Which muscle is affected in a IVth nerve palsy?
superior oblique affected
How does the eye present in a fourth nerve palsy?
Eye is unable to look down and in on affected side
vertical diplopia most marked on looking down and in
bilateral cases may be seen in head injury
Which muscle is affected in a VIth nerve palsy?
abducens palsy
how does the eye present in a 4th nerve palsy?
inability to abduct
eye may drift medially on affected side due to pull of medial rectus
What should you do a suspected VIIth nerve palsy?
May cause exposure hence
test corneal sensation
test bells phenomena
Describe the pupil relax pathways - light reflex?
LOOK UP PICS
RCG –> PTN –> EWN –> Inf Div III
RCG –> PTN –> EWN –> Inf Div III
Join between PTN of top and EWN of bottom one
Describe the pupil reflex pathways - near reflex ?
Pre striate cortex area 19
- -> EWN –> Inf Div III
- -> EWN –> Inf Div III
Which test is used to look for a RAPD (relative afferent pupillary defect)?
swinging flashlight test
What happens in the swinging light test in a RAPD?
Mild RAPD: affected pupil shows a weak initial constriction followed by a dilation to a greater size
Moderate RAPD: affected pupil shows a stable or unchanged level of constriction followed by dilation to a greater size
Severe RAPD: affected pupil shows an immediate dilation to a greater size
If both eyes were dysfunction no ‘relative’ defect would be seen
What conditions lead to a RAPD?
Optic nerve disorders - for example: glaucoma, orbital disease, optic neuritis
Retinal causes of RAPD - for example: retinal detachment, severe macular degeneration, intraocular tumour
What is the difference between a APD/RAPD?
APD - no direct or consensual response
RAPD - reduced light and consensual response, pupil dilates on the swinging light test
What is anisocoria?
unequal pupil sizes
What is an efferent pupillary defect?
III nerve or pupillary muscle affected
Loss of consensual and direct pupillary reflex in affected eye
Consensual and direct pupillary reflex in unaffected eye
What is Horner’s syndrome?
lesions of the sympathetic pathway
Describe the pupil in Horner’s syndrome?
affected pupil is smaller than normal
pupil inequality is more pronounced in the dark
patient may have neck scars, partial ptosis and the eye may appear to be sunken in (apparent enopthalmos)
What is Adie’s syndrome and how does it present?
patient is often young and has an efferent pupillary defect on direct and consensual testing with sluggish responses
pupil constriction on convergence is often slow but miosis will eventually occur
patient may demonstrate abnormal tendon reflexes
What are Argyll-Robertson pupils?
may be blind from congenital syphilis
pupils are often small and irregular with sluggish light responses and light near dissociation
How would a patient with traumatic mydriasis present?
dilated pupil
facial scars
signs of pupil rupture
