Visual loss & blindness Flashcards
List the causes of sudden visual loss
Vascular (vein/artery obstruction or haemorrhage)
Wet age related macular degeneration (ARMD)
Retinal detachment
Closed angle glaucoma
Stroke
Optic neuritis
What are the two important branches of the ophthalmic artery?
Posterior cillary and central retinal
Which branch of the ophthalmic artery supplies the retina?
Central retinal artery
What are the symptoms of central retinal artery occlusion?
Sudden severe vision loss
Painless
What are the signs of central retinal artery occlusion?
Relative afferent pupillary defect (RAPD)
Pale oedematous retina
Thread-like vessels
When might central retinal artery occlusion be painful?
When it is associated with giant cell arteritis
Central retinal artery occlusion is a type of stroke. T/F
True - often a warning sign for things to come
Which two underlying diseases can cause central retinal artery occlusion?
Carotid artery disease
Emboli from heart (rare)
How can central retinal artery occlusion be managed ophthalmically and vascularly?
Ophthalmic - if within 24 hours can try to convert occlusion to a branch artery with massage
Vascular - carotid doppler to locate source of emboli and management of other risk factors
How does branch retinal artery occlusion present?
Sudden visual field defect
Painless
What is amaurosis fugax?
Transient central retinal artery occlusion
What are the symptoms of amaurosis fugax?
Transient visual loss (“curtain coming down”)
Painless
5-10 minute duration with complete recovery
What are the signs of amaurosis fugax?
Typically normal fundus examination
How is amaurosis fugax managed?
Immediate referral to TIA clinic
Aspirin (if no contraindications)
Name a cause of transient visual loss
Migraine
How does migraine typically present in the context of ophthamology?
Transient visual loss followed by headache
What are the causes of central retinal vein occlusion?
Vascular (Virchow’s triad - hypertension, diabetes)
Ocular (Glaucoma - raised IOP)
What are the components of Virchow’s triad?
Stasis of blood flow (artherosclerosis)
Endothelial injury (hypertension)
Hypercoagulability
How does central retinal vein occlusion present?
Sudden severe visual loss
Painless
What are the signs of central retinal vein occlusion?
Retinal haemorrhages
Dilated tortuous veins
Disc and macular swelling
Cotton wool spots
How are central retinal vein occlusions treated?
Treatment of underlying cause
Monitor for the development of complications
Anti-VEGF
How do branch retinal vein occlusions present?
Visual field defect
Painless
Sudden
What is ischaemic optic neuropathy?
Occlusion of optic nerve head circulation
Which blood vessels are affected in ischaemic optic neuropathy?
Posterior ciliary arteries
How can ischaemic optic neuropathy be classified?
Arteritic
Non-arteritic
What is the cause of arteritic ischaemic optic neuropathy?
Inflammation (GCA)
What is the cause of non-arteritic ischaemic optic neuropathy?
Artherosclerosis
How does ischaemic optic neuropathy present?
Sudden
Profound vision loss
Swollen optic disc
Giant cell arteritis is a vasculitis affecting which size of vessels? Name the commonly affected vessels
Medium
Temporal
Posterior ciliary
How does vision loss occur in ischaemic optic neuropathy?
Ischaemia causes death of the optic nerve
How does ischaemic optic neuropathy appear on fundoscopy?
Pale & swollen optic disc
How does vision loss from GCA present?
Sudden vision loss
Associated with headache
Profound loss
Irreversible
After vision loss associated with GCA, what is the ultimate goal of treatment? What is the treatment?
Prevention of bilateral vision loss
High dose systemic steroids
How does GCA present?
Temporal headache Scalp tenderness Amaurosis fugax Jaw claudication Enlarged temporal arteries Raised inflammatory markers
Where do most haemorrhages within the eye occur?
Vitreous (i.e vitreous haemorrhages)
Haemorrhages within the eye come from abnormal blood vessels. T/F
False - can come from abnormal or normal vessels
Bleeding within the eye coming from abnormal vessels is associated with what? Name two cases where this might occur
Retinal ischaemia and new blood vessel formation
Diabetic retinopathy
Retinal vein occlusion
Bleeding within the eye coming from normal vessels is associated with what?
Retinal tear/detachment
How does a vitreous haemorrhage present?
Loss of vision with floaters
What are the signs of a vitreous haemorrhage?
Loss of red reflex
Haemorrhage on fundoscopy
How is vitreous haemorrhage treated?
Treat underlying cause
Vitrectomy (if non-resolving)
How does retinal detachment present?
Painless Loss of vision Flashing Floaters Halos around light
What are the signs of retinal detachment?
Relative afferent pupillary defect
Tear on fundoscopy
How is retinal detachment managed?
Surgical - laser or re-attachment
A retinal detachment within the inferior optic field will cause vision loss where within the visual field? Why?
Superiorly
Inversion of image
What is the commonest cause of blindness in the elderly (in the West)?
Age related macular degeneration
What are the two types of macular degeneration?
Wet
Dry
Both types of macular degeneration present with vision loss, what is the difference between the type of vision loss?
Wet - sudden
Dry - gradual
Describe the pathogenesis of wet age related macular degeneration
Blood vessels grow under the retina and leak fluid/blood causing scarring
How does wet ARMD present?
Rapid central vision loss
Distortion/metamorphopsia
Enlarged blind spot/scotoma
What are the signs of wet ARMD?
Haemorrhage/exudate over the macula (can only be seen when patient looking directly at you during ophthalmoscopy)
Which test can be done to check for ARMD, besides ophthalmoscopy?
Amsler grid
How is wet ARMD treated?
Anti-VEGF injected into vitreous cavity
How does anti-VEGF work?
Binds to vascular endothelial growth factor to stop neovascularisation
How does gradual vision loss present?
Usually bilateral
Asymmetrical
Early presentation - reduced visual acuity
Late presentation - visual field defect
What are the causes of gradual vision loss?
C - cataract A - age related macular degeneration (dry) R - refractive error D - diabetic retinopathy I - inherited disease G - glaucoma (open angle) A - access to eye clinic N - non-urgent
Name an inherited disease which causes gradual vision loss
Retinitis pigmentosa
What is a cataract?
Clouding of the lens
What are the causes of cataract?
Age Congenital Traumatic Metabolic Drug induced
Name a congenital cause of cataract
Intrauterine infection
Name a metabolic cause of cataract
Diabetes
Name a drug class which causes cataract
Steroids
Why is it important to check the red reflex in neonates?
Cataract risk due to intrauterine infection
How are cataracts treated? When are they treated?
Surgical removal with intra-ocular lens implant
If patient is symptomatic
How does dry age related macular degeneration present?
Gradual visual decline
Scotoma/central vision missing
What are the signs of dry ARMD?
Drusen
Atrophic portions of retina
What is drusen?
Build up of waste products below the retinal pigment epithelium
How is dry ARMD treated?
Supportive (vision magnifiers)
What do we call short sightedness?
Myopia
What do we call long sightedness?
Hypermetropia
What is astigmatism?
Eye shaped abnormally (like a rugby ball)
What is presbyopia?
Loss of accommodation reflex with aging
What is glaucoma?
Progressive optic neuropathy due to high intra-ocular pressure
How can glaucoma be categorised?
Closed angle
Open angle
What is the end point of glaucoma?
Vision loss due to optic nerve damage
When we refer to angles in glaucoma, which angle to we mean?
Iridocorneal angle
How does closed angle glaucoma present?
Painful eye Red eye Vision loss Headache Nausea & vomiting (due to pain)
How is closed angle glaucoma treated?
Lower IOP with eye drops or oral medication
How does open angle glaucoma present?
Asymptomatic
What are the signs of open angle glaucoma?
Cupped disc
Visual field defect
+/- high IOP
How is open angle glaucoma managed?
Lower IOP with - eye drops - laser - surgery REGULAR MONITORING IN GLAUCOMA CLINIC
