Loss of Vision Flashcards
what is central retinal artery occlusion?
something blocks the flow of blood through the central retinal artery which supplies blood to the retina and is a branch of the ophthalmic artery of the ICA
how does central retinal artery occlusion present?
sudden painless loss of vision, relative afferent pupillary defect (pupil affected constricts more when light shone), fundoscopy will show pale retinal with cherry red spot
how is central retinal artery occlusion treated?
chances of visual recovery is almost none so treat CVS risk factors
how does a branch retinal artery occlusion present?
sudden loss of vision, fundus examination will show paleness of the retina in a particular area - managed the same as CRAO
how does a central retinal vein occlusion present?
sudden loss of vision, fundus examination with show haemorrhages on the fundus of all 4 quadrants, maybe swelling of optic nerve or macula, associated with CVS risk factors
how is central retinal vein occlusion treated?
treat macular oedema and prevent complications- laser photocoagulation, intravitreal steroids (eg dexamethasone), anti-VEGF therapies
what is anterior ischaemic optic neuropathy?
sudden complete loss of vision which can be split into arteritic causes (giant cell arteritis) and non-arteritic causes
what will giant cell arteritis cause?
loss of vision, headache, loss of appetite, scalp and superficial temporal arteries tenderness, loss of pulsation
how is GCA managed?
high dose systemic steroids
what will non-arteritic cause?
much more common and the mechanism is unclear, painless and typically presents with altitudinal visual field loss (loss of half of the persons vision)
how is non-arteritic treated?
treat vascular risk factors and further ophthalmic and systemic complications
what are the possible causes of gradual vision loss?
cataract, glaucoma, age related macular degeneration, diabetic retinopathy
what is age related macular degeneration (AMD)?
degeneration in the macular causes a progressive deterioration of vision and is the most common cause of blindness in the UK - can be dry (90%) or wet (worse)
how does AMD present?
gradual worsening central visual field loss, reduced visual acuity, distortion of straight lines (Amsler grid test), drusen= key finding on fundoscopy= yellow deposits of proteins and lipids
how is AMD treated?
dry= no specific treatment but focus on lifestyle management wet= anti-VEGF medications
