Posterior Flashcards
(346 cards)
What is the pathogenesis of retinal vein occlusion
compression at AV crossings –> degenerative venous changes –> hypercoagubility
What are the risk factors of retinal vein occlusion? (9)
hypertension hyperlipidemia diabetes CVD increased IOP/glaucoma smoking high BMI CT disorders/sarcoidosis/lupus vasculitis
Symptoms of BRVO? (5)
may be asymptomatic onset often in morning transient vision loss metamorphopsia VF defects
Signs of acute BRVO (6)
located in one quadrant flame/dot-blot haemorrhages CW spots dilated, tortuous veins oedema ON swelling/hyperaemia
Signs of chronic BRVO (2)
venous collateral formation
vascular sheathing
What modalities should you use to investigate BRVO? (2)
Fluorescein angiography
OCT
BRVO complications (2)
macula oedema
vitreous haemorrhage
BRVO are urgently referred if acute and semi-urgently if chronic for a systemic work-up and consideration of what types of treatment? (3)
laser
intravitreal steroid
anti-VEGF Tx
What is the optometrists role in managing BRVO other than referral?
monitoring for signs of NV and assoc complications
What are the clinical features of CRVO? (7)
intra-retinal haemorrhage (all quadrants) venous engorgement and tortuosity optic disc swelling CW spots CMO sudden painless loss of vision presenting VA reduced
Pathogenesis of CRVO?
Compression of CRV at lamina cribosa either by thrombus or CRA
Ischaemic vs non-ischaemic CRVO
Ischaemic
- VA <6/60
- marked RAPD
- optic nerve swelling
- severe venous tortuosity
- risk of developing retinal and iris NV
Non-ischaemic
- more common
- VA >6/60
- minimal RAPD
- may convert to ischaemic
CRVO management? (4)
monitoring monthly for 1 year
thrombolytics
Laser chorioretinal anastomosis (L-CRA)
pan retinal photocoagulation
*possibly intra-vitreal anti-VEGFs
A person with CRVO has a better outcome when
present early and treated early
CRAO symptoms (3)
- painless vision loss over several seconds
- possible Hx of amaurosis fugax
- vision significantly reduced (<6/120) unless cilioretinal artery present
CRAO signs (4)
- VA <6/120 and RAPD in affected eye
- Within first few minutes retina may look normal
- ischaemic whitening of retina resulting in cherry-red spot at macula
- retinal arteriole thinning and attenuation with possible segmentation of blood flow
What is the level of urgency for CRAO?
ophthalmic emergency - urgent referral
Management for CRAO? (7)
- emergency referral
- digital ocular massage or with gonio
- reduction of IOP by paracentesis or pharmaceutically
- assessment of risk of GCA
- control of systemic disease (HT, diabetes, hyperchol)
- assessment of carotid and cardiac disease as source of emboli
- use of aspirin or warfarin
BRAO can occur secondary to what two things?
emboli
inflammation
Over 90% of BRAOs involve arteries in which area?
temporal retinal arteries
BRAO symptoms (2)
- acute, unilateral, painless loss of vision over several seconds
- visual field defect may be noticed
BRAO signs (4)
- VA <6/12 affected eye
- initially fundus looks normal within first few mins
- localised ishaemic whitening of retina in area fed by arteriole
- retinal arteriole thinning and attenuation with possible segmentation of blood flow
Management of BRAO (4)
- referral for assessment of systemic associations
- control of systemic disease as for CRAO
- assessment for carotid and cardiac disease as for CRAO
- majority of Px achieve 6/12 or better with conservative Tx
Which is more common: BRVO or CRVO?
BRVO