Loss of vision Flashcards
what are the 5 causes of sudden vision loss?
vascular cause vitreous haemorrhage retinal detachment WET ARMD closed-angle glaucoma
What are the causes of central retinal artery occlusion?
GCA
embolic
carotid artery disease
What are the signs of a central retinal artery occlusion?
RAPD
loss of red reflex
What is seen on fundoscopy in central retinal artery occlusion?
pale swollen retina
thin and narrow vessels
cherry red spot at macula
treatment for central retinal artery occlusion…
only effective within 12-24hrs
ocular massage
IV Diamox
anterior chamber paracentesis
What can cause central retinal vein occlusion?
Virchow’s triad
raised IOP
What are the signs of central retinal vein occlusion?
sudden painless visual loss
RAPD
What is seen on fundoscopy in central retinal vein occlusion?
red oedematous retina dilated vessels cotton wool spots retinal flame haemorrhages neovascularisation (if long-standing)
treatment for central retinal vein occlusion…
no ischaemia - observe in 3 months
ischaemia but no neovascularisation - observe in 4-6 wks
ischaemia and neovascularisation - urgent anti-VEGF
what is a vitreous haemorrhage?
haemorrhage into vitreous cavity
what can cause a vitreous haemorrhage?
abnormal vessels - DM
normal vessels - retinal tear
symptoms and signs of vitreous haemorrhage…
loss of vision
floaters
loss of red reflex
haemorrhage on fundoscopy
treatment for vitreous haemorrhage…
identify cause
virectomy if non-resolving
What is a retinal detachment?
separation of vitreous gel from retina
leads to retinal tear and then detachment
symptoms and signs of a retinal detachment…
painless loss of vision
flashing lights and floaters
dark shadow in peripheral vision
RAPD
Treatment for retinal tear…
laser of tear to prevent detachment
if retina detached - surgery
what is wet age-related macular degeneration (ARMD)?
abnormal, new vessel growth that can haemorrhage and leak into macula area
symptoms and signs of wet ARMD…
sudden central vision loss
metamorphopsia
what is seen on fundoscopy in wet ARMD?
red pool of blood
pale grey oedematous macula
tx for wet ARMD…
anti-VEGF intra vitreal injection
What are the causes of gradual vision loss?
Cataract ARMD (dry) Refractive error Diabetic retinopathy Inherited disorders Glaucoma (open-angle)
what is a cataract?
opacification of crystalline lens
symptoms and signs of cataracts?
gradual painless vision loss
haloes flares
loss of red reflex
white pupil
tx for cataracts…
surgery
what is the commonest cause of blindness?
dry ARMD
what causes dry ARMD?
wear and tear of retinal pigment epithelium
symptoms and signs of dry ARMD…
drusen deposition around macula
gradual central vision loss
treatment for dry ARMD…
no active tx
visual aids
blind registration
What happens in diabetic retinopathy?
damage to blood-retina barrier causing occlusion of blood vessels and leakage into retinal circulation and neovascularisation
what investigation is done in diabetic retinopathy?
fundoscopy
treatment for diabetic retinopathy…
glycaemic control
laser photocoagulation
anti-VEGF, focal laser
what is the second most common cause of blindness?
open angle glaucoma
what is an open angle glaucoma?
iridocorneal angle is open but there is no obstruction
dysfunction in outflow of aqueous humour
symptoms of open angle glaucoma…
asymptomatic
slow painless vision loss
untreated- peripheral then central vision loss
what are 2 diagnostic signs for open angle glaucoma?
raised IOP
optic disc cupping
Tx for open angle glaucoma…
prostaglandins beta-blockers sympathomimemtics carbonic anhydrase inhibitors pilocarpine surgery - trabeculectomy