Visual loss Flashcards
visual loss can be sudden or gradual, give sudden causes
vascular occlusion vitreous haemorrhage retinal detachment wet ARMD closed angle glaucoma optic neuritis stroke
visual loss can be sudden or gradual, give gradual causes
cataracts dry ARMD open angle glaucoma refractive errors diabetic retinopathy
what is the main arterial supply to the eye and what does it branch from
ophthalmic artery from the internal carotid artery
what are the branches of the ophthalmic artery and what do they supply
posterior ciliary arteries - head of optic nerve
central artery of the retina - inner 2/3rd retina
what is CRAO
central retinal artery occlusion
symptoms of CRAO
painless sudden loss of vision
signs of CRAO
RAPD
pale oedematous retina
cherry red spot at fovea
thin vessels
causes of CRAO
stroke
carotid artery disease
thromboembolic
types of CRAO
central
branch
amaurosis fugax
what is amaurosis fugax
transient CRAO
visual loss like a ‘curtain coming down’
no abnormalities on examination - rely on history
urgent stroke referral
what is CRVO
central retinal vein occlusion
symptoms of CRVO
sudden visual loss
CRVO is associated with Virchow’s triad, what are the elements of this
hypercoaguability
stasis
endothelial damage
signs of CRVO
retinal haemorrhages
dilated tortuous veins
swelling of disc and macula - oedematous
cotton wool spots = infarcts of nerve fibre layer
buzzword description of CRVO appearance
cheese on toast appearance
types of CRVO
central
branch
what is ischaemic optic neuropathy
occlusion of optic nerve head
what vessel is occluded in ischaemic optic neuropathy
posterior ciliary arteries
causes of ischaemic optic neuropathy
GCA
symptoms of ischaemic optic neuropathy
sudden visual loss
may be irreversible
GCA symptoms - headache, jaw claudication, scalp tenderness…
management of GCA with ocular involvement
high dose steroids ASAP
causes of intra ocular haemorrhage
diabetic retinal ischaemia
CRVO
Hypertensive disease
what do you call bleeding into the vitreous cavity
vitreous haemorrhage
signs and symptoms of vitreous haemorrhage
sudden loss of vision
floaters
loss of red reflex
haemorrhages on fundoscopy
features of optic neuritis
painful loss of vision
associated with MS
RAPD
reduced colour vision
pathology behind retinal detachment
vitreous gel becomes more like liquid and collapses in on itself pulling and tearing the retina away resulting in a mechanical separation of sensory retina from pigmented epithelium
symptoms of retinal detachment
sudden painless loss of vision
sudden onset flashers and floaters
signs of retinal detachment
RAPD
may see detachment
risk factors for ARMD
smoking
age
genetics
diet
in wet ARMD, which is lost first, central or peripheral vision
central vision is lost first
pathology behind wet ARMD
neovascularisation under retina
new vessels are fragile and leaky and so can bleed under the retina
symptoms of wet ARMD
rapid central visual loss
distortion aka metamorphopsia
signs of wet ARMD
haemorrhages
exudate
drusen
what is glaucoma
progressive optic neuropathy usually from raised intra ocular pressure from build up of aqueous humour
symptoms of closed angle glaucoma
painful red eye severe headache N+V cloudy cornea dilated pupil peripheral vision lost first
in closed angle glaucoma, which is lost first, central or peripheral vision
peripheral vision is lost first
features of gradual visual loss
bilateral
asymmetrical
CARDIGAN mneumonic for gradual visual loss
cataracts ARMD dry refractive error diabetic retinopathy inherited glaucoma - open angle Access is Non urgent
what are cataracts
cloudiness of lens from build up of proteins
there are many different types
what investigation should be done in all babies to rule out congenital catarcts
red reflex
symptoms of cataracts
gradual loss of vision uncorrected by glasses
glare from TV or street signs/lights
management of cataracts
phacoemulsification and lens replacement surgery
pathology behind dry ARMD
build up of drusen around macula which interrupts nutrient exchange damaging the retina
symptoms of dry ARMD
gradual loss of vision
central vision missing - scotoma
signs of dry ARMD
drusen
atrophic patches of retina
what can you do to fix refractive error
get glasses
features of open angle glaucoma
asymptomatic, found on screening
cupped optic disc (bigger cup, greater damage)
loss of peripheral vision
raised IOP
what is the difference between a swollen optic disc and papilloedema
swollen optic disc can be from any cause
papilloedema is a swollen disc secondary to only raised ICP
what should you suspect in patients with bilateral optic disc swelling
raised ICP due to SOL
what is the normal ICP range
5-15mmHg
the optic nerve is an extension of the brain and so is covered by the 3 layers of meninges, true or false
true
what 3 components influence the ICP
brain
blood
CSF
what happens as a consequence of chronic optic disc swelling
optic atrophy
atrophic and pale looking disc
visual loss –> blindness
if there is horizontal visual loss, the vascular defect is infront/behind the optic chiasm
infront
if there is vertical visual loss, the vascular defect is infront/behind the optic chiasm
behind
causes of CRVO
hypertension raised cholesterol myeloma - hyperviscosity inflammation Virchows triad
management of wet ARMD
anti VEGF intra vitreal injections
management of closed angle glaucoma
miopics and iridotomy with laser therapy
