Sudden visual loss can have a vascular aetiology. Whhich two things does this include?
Occlusion of which two circulations may induce sudden visual loss?
- Retinal circulation
- Optic nerve head circulation
Haemorrhage from which causes may induce sudden visual loss?
- Abnormal new blood vessels
- Retinal tears
Which common conditions can cause the development of abnormal new vessle growth?
- Wet macular degeneration
- Diabetic retinopathy
The retina has a vascualr supply from which two sources?
- Central retinal artery
- Choroid (outer 1/3rd)
What are the classic symptoms of a central retinal artery occlusion (CRAO)?
- Sudden profound visual loss
Which classic sign of a CRAO can be seen in the pupils?
Relative afferent pupil defect
How can a CRAO be identified on a fundoscopy?
- Pale oedematous retina
- Thread-like retinal vessels
- Cherry red spot
What may induce a CRAO?
- Carotid artery disease
- Emboli from heart (rare)
How can a CRAO be treated?
If presents within 24hrs ocular massage
Transient CRAO is known by which other name?
What should happen with a patient who presents with amaurosis fugax?
- Urgent referral to stroke clinic
How is the vision loss associated with a transient CRAO different from that associated with a migraine?
It is painless
What are the different causes for a central retinal vein occlusion?
- Systemic - Atherosclerosis, hypertension, hyperviscosity (Virchow's triad)
- Ocular - Raised IOP
What are the symtoms of of a CRVO?
- Sudden, moderate/severe visual loss
What signs on a fundoscopy are characteristic of a CRVO?
- Retinal "flame" haemorrhages
- Dilated tortuous veins
- Disc and macular swelling
What are the treatments for a CRVO?
- Anti-VEGF therapies
- Address underlying risk factors such as diabetes or hypertension
- Laser therapies to target new vessel growth
Which arteries become occluded in ischaemic optic neuropathy?
Posterior ciliary arteries
What are the two forms of ischaemic optic neuropathy?
- Arteritic (inflammation)
- Non-arteritic (atherosclerosis)
Which condition causes arteritic ischaemic optic neuropathy?
Giant cell arteritis
How does the optic disc present in a patient with ischaemic optic neuropathy?
What are the symptoms associated with arteritic ischaemic optic neuropathy?
- Sudden profound vision loss
- Irreversible blindness
Which symptoms are closely associated with giant cell arteritis?
- Tender enlarged temporal artery
- Jaw claudication
- Scalp tenderness
- Amaurosis fugax
What are the symptoms of a vitreous haemorrhage?
- Loss of vision
What are the signs of vitreous haemorrhage?
- Loss of red reflex
- Haemorrhage seen on fundoscopy
How are non-resolving cases of vitreous haemorrhage managed?
What are the symptoms of a retinal detachment?
- Painless loss of vision
- Sudden onset of flashes and floaters
What are the signs of retinal detachment?
- May have relative afferent pupil defect
- May see tear on opthmaloscopy
Which type of treatment is usually required in a retinal detachment?
What is the most common cause of blindness in the western world?
Age related macular degeneration