Week 2 - D - Ophthamology 3 - Sudden visual loss causes Flashcards
Name some causes of sudden visual loss
Central retinal artery occlusion
Central retinal vein occlusion
Retinal detachment
Vitreous hameorrhage
Transient central retinal artery occlusion
Wet age-related macular degeneratiion
• Pale oedematous retina, thread-like retinal vessels What is this?
Central retinal artery occlusion
What is the main cause of central reitnal artery occlusion? How does the patient present?
Usually carotid artery disease
Paitent presents with profound painless sudden vision loss
Why is there a cherry red spot at the fovea in centra retinal artery occlusion?
The macula is thin and the choroidal blood supply can be seen through the cells of the macula
If the patient presents within 100 minutes with a central retinal artery occlusion, what is the treatment?
Try an ocular massage to move the embolism in the artery from the central to branched retinal artery
Patients rarely recover from CRAO, how is the source of the embolism attempted to be established?
Try using a doppler to identify the location
Doppler is used for arteries and viens
Describe how a patient with a tranisent ischaemic attack would present? What is another name for the transient ischaemic attack of the eye?
Amaurosis fugax
Presents with a sudden painless loss of vision, which is only temporary and is like a curtain coming down over the eye
Immediate referral TIA clinic for amurosis fugax, what drug is given? What can a TIA be a sign of?
Give the patient aspirin
Can be a precursor to stroke
How does apsirin work?
It works by the inhibiting the acitvation COX enzyme (cyclo-oxygenase) which is required for prostoglandin (induces fever) and thromboxane (clotting) synthesis
The major blood supply to the eye are via branches of which artery?
Via branches of the ophthalmic artery which is branch of the internal carotid artery (ICA)
What type of visual defect will this cause? What is this?
This is a branched retinal artery occlusion
Will most likely cause an inferior visual defect as the superior retina has the defect
Describe the findings for central retinal vein occlusion? (fundoscopy findings as well)
Sudden vision loss
On examination has dilated torturous veins and retinal haemorrhages
Also has a swollen optic disc and macular swelling
What is the treatment for central retinal vein occlusion?
treatment would be an anti VEGF (anti vascular endothelial growth factor)
If patients develop complications due to development of new vessels in CRVO, what may be given to prevent vitreous haemorrhage? (can lead to glaucoma)
Patient may be given laser therapy to prevent vitrous haemorrhage but only if neovascularisation is present
What are the usual causes of CRVO? (virchow’s triad)
Hypercoagulability
Stasis of blood
Endothelial damage
Which aartery supplies the optic nerve head?
The posterior ciliary arteries
Occlusion of the posterior ciliary arteries may lead to what?
This may lead to ischaemic optic neuropathy
There are two type, arteritic and non-arteric ischaemic optic neuropathy
What is arteritic ischameic optic neuropathy caused by? What is non arteritic caused by?
Arteritic is caused by inflammatory processes such as Giant cell arteritis
Non- arteritic - due to astherosclerosi eg hypertension, hyperlipidaemia
sudden, profound visual loss is present in ischaemic optic neuropathy How does the optic disc look on fundoscopy?
Looks swollen and pale retina
How does giant cell arteritis present?
Presents with a headache and jaw claudication, scalp tenderness (when coming hair) and sudden visual loss if it affects the eye
What is the immediate treatment for giant cell arteritis?
Give oral prednisolone: For people with visual symptoms — 60 mg as a one-off dose (they should be seen by an ophthalmologist the same day).
For people without visual symptoms — 40 to 60 mg daily (minimum 0.75 mg/kg).
What is giant cell arteritis also known as and describe how the associated disease presents?
AKA Temporal arteritis
Presents with myalgia in the hip and shoulder girdles with accompanied morning stiffness lasting greater than 1hour - the associated condition is known as polymyalgia rheumatica
Steroids are given in GCA before a biopsy is taken to confirm, why may a biopsy be negative? What markers may be raised in GCA?
may be negative due to skip lesions in GCA
ESR, PV and CRP will be raised in GCA
In GCA, what age group is it typically seen in? What percentage of patients does it associate with polymyalgia rheumatica?
Typically seen in patients over 50 and seen in 50% of patients with PMR
Why is there jaw claudication in giant cell arteritis?
this is because there may be inflammation of the maxillary artery meaning when chewing there is no blood supply and therefore pain
Sudden loss of vision “Floaters” Loss of red reflex What is this likely to be?
Vitrous haemorrhage
What two other pathologies is vitreous haemorrhage associated with as a cause of the new vessel formation leading to haemorrhaging?
Associated with central retinal vein occlusion causing ischaemia and therefore new vessels arise
And associated with proliferative diabetic retinopathy where new leaky vessels arise
What is the treatment for non resolving vitreous haemorrhge?
Vitrectomy
• Painless loss of vision • Sudden onset of flashes/floaters (mechanical separation of sensory retina from retinal pigment epithelium)
What is this? What is the flashes known as?
This is retinal detachemnt
The flashes are known as photopsia
What can often be the cause of retinal detachment?
Vitreous detachment bringing the retinal layer with it
Retinal detachment usually requires surgical treatment
• New blood vessels grow under retina – leakage causes build up of fluid/blood and eventually scarring • Rapid central visual loss What is this?
Wet age related macular degeneration
What is the difference of the macula on fundoscopy in wet and dry age related macular degenration?
Wet - can see bleeding and scrring over macula in right pic
Dry - can see drusen spots around the macula on left pic
What is the distortion known as in wet- age related macular degeneration?
Metamorphopsia
What is the treatment for wet ARMD?
• Anti-VEGF treatment – injected into vitreous cavity.
Stops new blood vessels growing by binding to VEGF (vascular endothelial growth factor)
