Flashcards in Visual Loss Deck (45)
List the main causes of sudden visual loss
Wet age-related macular degeneration
What are the 2 main branches of the ophthalmic artery?
Central retinal artery
Posterior ciliary artery
Which part of the retina does the central retinal artery supply?
Inner 2/3 (including ganglion cells)
Which part of the retina does the posterior ciliary artery supply?
Outer 1/3 (photoreceptors, pigment layer)
Visual loss caused by central retinal artery occlusion is associated with pain. True/False?
Painless unless assoc. with GCA
Relative afferent pupillary defect is evident in central retinal artery occlusion. What is this?
When a light is shone on the right eye, the right eye constricts but the left eye dilates
Describe the appearance of the retina in central retinal artery occlusion
Outline ophthalmic management of central retinal artery occlusion within 24hrs
Ocular massage (try to convert CRAO into BRAO)
Outline vascular management of central retinal artery occlusion
Carotid Doppler (establish source)
Manage risk factors
What is another name for transient central retinal artery occlusion?
Describe visual loss in amaurosis fugax
Transient/partial loss "like a curtain" that lasts up to 5mins with full recovery
Amaurosis fugax patients require immediate referral to which clinic?
List causes of central retinal vein occlusion
Raised intra-ocular pressure
How does atherosclerosis cause central retinal vein occlusion?
Arterial thickening presses on vein to cause altered blood flow, resulting in stasis and occlusion
Describe the appearance of the retina in central retinal vein occlusion
Dilated, tortuous veins
Which growth factor may be suppressed as part of treatment for central retinal vein occlusion?
The retina appears pale in central retinal artery occlusion and dark in central retinal vein occlusion. True/False?
Give another name for occlusion of the optic nerve head
Ischaemic optic neuropathy
Describe the pathogenesis of ischaemic optic neuropathy
Posterior ciliary arteries become occluded which results in infarction of the optic nerve head
What are the 2 types of ischaemic optic neuropathy?
Arteritic (painful, inflammation, GCA)
Non-arteritic (painless, atherosclerosis)
What are the 4 stages of visual loss, defined by testing?
Directional hand movement
Perception of light
Blindness in giant cell arteritis is irreversible. True/False?
List clinical features of giant cell arteritis
Pulsating temporal artery
List clinical signs of a vitreous haemorrhage
Sudden visual loss
Loss of red reflex
How is a vitreous haemorrhage managed?
Identify + treat cause
Vitrectomy for non-resolving cases
List clinical features of retinal detachment
Painless visual loss
Flashes of light, floaters
Relative afferent pupil defect
What is the commonest cause of blindness in the Western world in patients over 65?
Age-related macular degeneration (ARMD)
What is the difference between the two types of ARMD?
Wet - sudden visual loss
Dry - gradual visual loss
Describe the pathogenesis of wet ARMD
Angiogenesis under the retina with leakage/build up of fluid