Visual Loss and Blindness Flashcards
Which artery supplies the inner 2/3rds of the retina?
Central retinal artery
Which arteries supply the optic nerve head?
Posterior ciliary arteries
Central retinal artery occlusion causes sudden/gradual painless/painful vision loss
Causes sudden painless vision loss
What light reflex is defective in central retinal artery occlusion?
Relative afferent pupil defect
What is the commonest cause of central retinal artery occlusion?
Plaque in the carotid artery
How should a central retinal artery occlusion be managed ophthalmically?
Ocular massage (convert central retinal artery occlusion to branch retinal artery occlusion)
If a patient says ‘a curtain is coming down’ on their vision what should be suspected?
Amaurosis fugax - transient central retinal artery occlusion
Give some signs of central retinal vein occlusion
Retinal haemorrhages
Disc swelling
Macular swelling
How can central retinal vein occlusion be treated?
Laser treatment
Anti-VEGF
In an arterial occlusion the retina is dark/pale while in a venous occlusion the retina is dark/pale
Arterial - pale
Venous - dark
What is occlusion of optic nerve head circulation known as?
Ischaemic optic neuropathy
What are the two common causes of ischaemic optic neuropathy?
Giant cell arteritis
Atherosclerosis
Give some symptoms of giant cell arteritis
Temporal headache
Scalp tenderness
Jaw claudication
How is giant cell arteritis treated?
Immediate high dose steroids
What is a vitreous haemorrhage?
Haemorrhage into the vitreous cavity
Give some signs of vitreous haemorrhage
Loss of red reflex
Floaters
Haemorrhage on fundoscopy
How can retinal detachment occur?
Vitreous becomes less gel-like causing the retina to pull in on itself and detach
Give some signs of retinal detachment
Sudden onset of flashes/floaters
Tear on ophthalmoscopy
What is the commonest cause of blindness in elderly patients in developed countries?
Age-related macular degeneration
What are the two types of ARMD?
Wet and dry
What occurs in wet ARMD?
New blood vessels grow under retina which leak causing fluid build-up
How is wet ARMD treated?
Anti-VEGF
What is glaucoma?
Effectively damage to the optic nerve resulting in visual loss
What are the main two types of glaucoma?
Open-angle and closed angle
What occurs in closed-angle glaucoma?
Aqueous build up between iris and lens causing the iris to be pushed forward blocking off trabecular meshwork and preventing aqueous drainage`
Closed-angle glaucoma is an ophthalmic emergency. True/false?
True
How do patients with closed-angle glaucoma present?
Painful red eye
Visual loss
Nausea
Give some causes of sudden visual loss
Closed angle glaucoma Vitreous haemorrhage Retinal detachment Wet ARMD Central retinal artery/vein occlusion Ischaemic optic neuropathy
What is a cataract?
A cloudiness of the lens
Give some symptoms of cataract
Gradual vision decline
Glare
What occurs in dry ARMD?
Drusen (waste products) build up and pull retina away from choroid
What occurs in open-angle glaucoma?
Resistance to outflow of aqueous in trabecular meshwork
How is any glaucoma treated?
Aim to preserve vision by lowering IOP
Give some examples of refractive error
Myopia (short-sighted)
Hypermetropia (long-sighted)
Presbyopia (loss of accommodation with ageing)
Give some causes of gradual vision loss
Cataract
Dry ARMD
Refractive error
Open angle glaucoma
