Visual loss and blindness Flashcards
What are the symptoms of central retinal artery occlusion?
Sudden painless profound visual loss
What does the fundus look like in CRAO?
Pale retina, thread-like vessels
What is an afferent pupillary defect?
One eye is less sensitive to light and does not constrict as much during the swinging light test (seen in CRAO)
Which aetiology accounts for about 80% of CRAOs?
Atherosclerotic thrombosis (carotid artery disease)
When would emboli from the heart be considered as a cause for CRAO?
In younger patients with valvular defects
What is the aim of ocular massage in CRAO? When should this be attempted?
Attempts to dislodge the blockage. Within 24 hours of presenting
How does branch retinal artery occlusion differ from central?
Loss of field of vision/retinal paleness in an area corresponding to the blocked branch
What is amaurosis fugax? How is it managed?
Transient painless visual loss, lasts around five minutes. Aspirin and immediate referral to TIA clinic
What is the most common cause of central retinal vein occlusion?
Thrombus formation
What are the clinical features of CRVO?
Sudden, moderate-to-severe visual loss
Retinal haemorrhage
Dilated, tortuous veins
Disc swelling and macular swelling
How is CRVO treated?
Management of underlying cause (systemic e.g. diabetes, hypertension. Or ocular- glaucoma)
Monitor for complications of new vessel formation
Anti-VEGFs may be used
How do artery and vein occlusions differ on fundoscopy?
Arterial occlusions are pale with thin threadlike vessels; venous occlusions are dark with thick, tortuous dilated vessels
The occlusion of which arteries leads to infarction of the optic nerve head? (ischaemic optic neuropathy)
Posterior ciliary arteries
What are the two sub-types of ischaemic optic neuropathy?
Arteritic (GCA)
Non-arteritic (atherosclerotic)
How does ION present?
Sudden profound visual loss with swollen disc
How does temporal arteritis/GCA present?
Temporal headache; jaw claudication; scalp tenderness; amaurosis fugax; malaise; very high ESR, PV and CRP
How is GCA treated? What does this hope to achieve?
Immediate high-dose systemic steroid- prevent visual loss in the other eye
In vitreous haemorrhage, where does bleeding occur from?
Abnormal vessels i.e. in diabetic retinopathy, or after retinal vein occlusion
From retinal vessels, usually after a retinal tear
What are the symptoms/signs of vitreous haemorrhage?
Loss of vision, “floaters”, loss of red reflex
What is retinal detachment?
Separation of the sensory retina from the retinal pigment epithelium
What are the symptoms/signs of retinal detachment?
Painless loss of vision (sometimes described as like a curtain coming down)
Photopsia (“flashing lights”)
May have RAPD
May see retinal tear on opthalmoscopy
How do wet and dry ARMD differ with regards to visual loss?
Usually gradual in dry; often rapid in wet
What other visual symptom is commonly seen in ARMD?
Metamorphosia (distortion)
How is wet ARMD treated?
Intravitreal antiVEGF injections
What does CARDIGAN stand for?
Acronym for causes of gradual visual loss
Cataract ARMD (dry) Refractive error Diabetic retinopathy Inherited disease Glaucoma Access Non-urgent
How does gradual visual loss usually present?
Early- with reduced visual acuity
Late- sometimes reduced field
Usually bilateral
Often asymmetrical
How is cataract managed?
Surgical removal with lens implant if patient is symptomatic
What is cataract?
Opacification of the lens
How does dry ARMD present? What signs are seen in fundoscopy?
Gradual decline in vision; central part of vision can be “missing”.
Signs- drusen (patches of protein/lipid exudate) on the retina
What are the four categories of refractive error?
Myopia (short-sightedness- caused by focussing of the image “in front” of the retina)
Hypermetropia (long-sightedness- caused by focussing of the image “behind” the retina)
Astigmatism- usually due to irregular cornea curvature
Presbyopia (loss of accommodation with ageing)
What are the signs of open angle glaucoma?
Increased intra-ocular pressure
Cupped disc
Visual field defect
How is open-angle glaucoma treated?
Pressure-lowering eyedrops
Occasionally surgery
Regular monitoring
What distinguishes wet ARMD from dry?
Choroidal neovascularization
