Topic A2 Flashcards
(24 cards)
What are some of the general symptoms of Retinal Artery/Vein Occlusions?
1) Loss of Peripheral Vision
2) Blind Spots
3) Floaters
4) Blurry Vision
What are the causes of Retinal Artery Occlusions?
Blockages in the artery/arteries due to
1) Clot
2) Embolism - the “broken apart” parts of a clot/the matter causing the blockage
3) Build-up of cholesterol in any artery
What is the appearance of a CRAO?
A cherry red spot
- reddish foveola on a pale retina
- due to choroidal blood circulation below fovea
What are the signs & symptoms of CRAO?
*Hint - 9
1) Early attacks of Amaurosis Fugax
- Sudden & temporary loss of vision
2) Sudden painless loss of vision to light perception/counting fingers over seconds
3) RAPD
4) Arterial Narrowing
5) Retinal Hole/ Ischemia
6) Retina whitens with a cherry red spot within HOURS
7) VF defects
8) Optic atrophy
9) Presence of cilioretinal artery
- to help preserve macular function for central vision
What is the management guidelines for CRAO?
1) Immediate referral
- rapid intervention within 90 min
2) Treatment includes
- Reducing IOP
- surgical removal of emboli
- Vasodilation = widening of BV to relax its muscular walls and increase O2 supply & dislodge emboli
What is the etiology for BRAO?
1) Similar to CRAO but its visual prognosis is 6/12 or better
2) Embolus small enough to pass through laminar region & to be lodged @ an arterial branch
3) common @ superotemporal retina
What are the signs and symptoms of BRAO?
1) Early attacks of Amaurosis Fugax
2) Distribution is dependent on location of affected BV
3) Arterial Narrowing
4) Retinal Hole
5) Retina whitens cause of hypoxia within hours
- this only occurs to the areas surrounding the affected arterial branch
What is the management guidelines for BRAO?
1) Immediate Referral
2) Treatment similar to CRAO
-
What is the management guidelines for BRAO?
1) Immediate Referral
2) Treatment similar to CRAO
- Reducing IOP
- surgical removal of emboli
- Vasodilation = widening of BV to relax its muscular walls and increase O2 supply & dislodge emboli
What causes Venous Occlusive Diseases?
Blockage in the veins caused by a clot (thrombus)
What happens in BRVO & what causes it?
(Basic/General answer is sufficient)
1) A thrombus occurs @ arteriovenous crossing points
2) causes compression & occlusion of retinal vein
What happens in CRVO?
(Basic/General answer is sufficient)
A thrombus occludes the CENTRAL retinal vein near the lamina cribrosa?
What are the risk factors for venous occlusive diseases?
1) Age - >65 y/o
2) Hypertension
3) Hyperlipidemia
4) Diabetes
5) Glaucoma & Ocular Hypertension
What is the most common cause for BRVO?
Systemic Hypertension
What are the symptoms of BRVO?
** Depends on the location on occlusion
1) Macula - sudden painless onset of blurred vision & metamorphopsia
2) Peripheral - Asymptomatic
What are the signs of BRVO?
** Depends on the location on occlusion
1) Dilation & tortuosity of affected region
2) Flame-shaped haemorrhages
3) Dot-blot haemorrhages
4) Retinal &/or macular oedema
5) CWS
6) supertemporal quadrant is commonly affected
7) Retinal neovasc. in 8% of eyes in 3 years
8) NV @ disc (other places is possible too)
- Risk of tractional RD
What is the symptoms of non-ischemic CRVO?
1) Sudden painless monocular decreasing in vision
2) VA varies based on severity
- Eyes w good VA = good prognosis
- Eyes VA worse than 6/60 = may lead to ischemia CRVO
3) RAPD - absent/mild
What is the symptoms of non-ischemic CRVO?
1) Sudden painless monocular decreasing in vision
2) VA varies based on severity
- Eyes w good VA = good prognosis
- Eyes VA worse than 6/60 = may lead to ischemia CRVO
3) RAPD - absent/mild
What are the signs of non-ischemic CRVO?
1) Dilated & Tortuous veins
2) Flame-shaped haemorrhages
3) Dot-blot haemorrhages
4) Optic disc & macular oedema
5) CWS - esp in px w hypertension
** more common
What happens in ischemic CRVO?
There will be a rapid onset of venous obstructions that will
- reduce retinal blood flow
- capillary closure
- retinal hypoxia
What are the symptoms of ischemic CRVO?
1) Sudden & severe monocular painless visual impairment
2) VA = Counting Fingers
- poor visual prognosis due to macular ischemia
3) RAPD
What are the signs of ischemic CRVO?
1) “Blood & thunder” fundus
2) Severe tortuosity & engorgement of vein
3) Extensive flame-shaped haemorrhage
4) Extensive dot haemorrhages
5) Severe disc swelling & hypertension
6) Neovasc. @ iris
Aka rubeosis iridis
7) Neovasc. @ retina
What are the 4 tests to find out the difference between non-ischemic & ischemic CRVO?
1) VA - eye w CRVO will have a VA worse than 6/120
2) Peripheral VF
- Non-ischemic CRVO: Sensitive to small & dim target
- Ischemic CRVO: Only able to see large & bright target
3) RAPD
- Non-ischemic CRVO: 97% of eyes had a RAPD of < 0.6 log units
- Ischemic CRVO: 94% of the eyes had a RAPD of > 0.9 log units
4) Electroretinography - To look at the amplitude of the B-wave to differentiate b/w ischemic & non-ischemic CRVO
- Best test with the best sensitivity & specificity
What are the management guidelines for BRVO & CRVO?
1) Anticoagulants to prevent thrombus propagation
2) Pan retinal photocoagulation (PRP) to prevent neovasc.
