Visual loss Flashcards
(42 cards)
what ‘ABCD’ causes sudden visual loss
A: ARMD (wet), B: bleed/ blocked vessel (vitreous haemorrhage, occlusion), C: closed angle glaucoma, D: detached retina
what is the most common cause of blindness in the UK
age related macular degeneration
what is the pathophysiology of wet ARMD
abnormal new vessels grow under retina (choroid) mediated by VEGF, leakage causes fluid build up (oedema) which leads to scarring
what are symptoms (4) and signs (3) of wet ARMD
rapid central visual loss / blind spots (scotoma) / distortion (metamorphosia) / decreased brightness of colours / haemorrhage and hard exudates on retina (normal colour) / DRUSEN: yellow deposits of proteins and lipids / atrophic retina
how do you identify wet vs dry ARMD
OCT scan - drusen a key identification for ARMD
how do you treat wet ARMD
intravitreal injections and anti VEGF eg ranibizumab
what can causes a central retinal artery occlusion (CRAO)
carotid artery disease - (hypertension, stroke, atherosclerosis), emboli
what are symptoms (2) and signs (4) of a CRAO
sudden visual loss / painless / pale and oedema retina / thread like vessels, cherry red macula / (relative afferent pupil defect - pupils dilate in affected eye - must be V severe)
what is a brach retinal artery/ vein occlusion (BRA/VO)
branch off of central retinal artery/ vein - not as severe as not an end artery so not whole of retina is ischaemic
what is amaurosis fugax
transient painless visual loss / black curtain loss for a few minutes / usually from emboli
what is virchow’s triad
hypercoaguble state (eg cancer) /abnormal flow (eg hypertension) / endothelial damage (eg diabetes)
what are symptoms and signs of central retinal vein occlusion (CRVO) (5)
sudden visual loss / retinal haemorrhages / dilated torutous veins / disc swelling (hard to see cup and cone) and macular swelling /cotton wool spots (ischamia)
what is occlusion of optic nerve head
AKA ischaemic optic neuropathy (ION) - posterior ciliary arteries which are blood supply to CNII become occluded
what are symptoms and signs of ischaemic optic neuropathy (3)
sudden, painless visual loss, swollen optic disc
what is ION associated with
temporal arteritis (polymyalgia rheumatica, headache, claudication, tenderness)
what is a vitreous haemorrhage
bleeding from vessels into vitreous
what can cause vitreous haemorrhage
abnormal vessels from neovascularisation / new vessels eg retinal tear
what are symptoms and signs of a vitreous haemorrhage (4)
loss of vision / floaters / loss of red reflex / haemorrhage on fundoscopy
what is a closed angle glaucoma
increased pressure in eye from build up aqueous fluid/ blocked trabecular drainage network AND iris blocks access to drainage (closed angle)
what are symptoms of closed angle glaucoma
(emergency), VV intense eye pain and headache / nausea and vomiting / sudden visual loss and halos / Females
what are signs of closed angle glaucoma
acute red eye / cloudy cornea / dilated pupil (high pressure causes ischaemia and sphincter muscles cant contract)
how do you treat closed angle glaucoma
zap hole in iris with laser, drugs: pilocarpine (miotic that constricts pupil), acetazolamide is a carbonic anhydrase inhib that reduces aqueous production)
what can cause retinal detachment
with age vitreous becomes watery and can get in behind retina and pull it away
what are symptoms of retinal detachment
painless, sudden visual loss / sudden FLASHES and FLOATERS of light in periphery / floaters
