Retinal Vascular disease

Question 1

What is the dual blood supply of the retina?

Answer 1

inner retinal layers are made up of the NFL (nerve fibre layer) to the INL (inner nuclear layer).

inner retinal layers supplied by the CRA
and drain through the CRV

Outer retinal layers
Outer Plexiform Layer(OPL) to RPE

Supply: Choriocapillaries
(via PCA) Drainage: Vortex veins

Question 2

What are the 3 signs of leakage in RVD?

Answer 2

1. haemorrhage

2.oedema

3. hard exudates

Question 3

Answer 3

microanurysms

between IPL/INL layers

Question 4

What is CRVO?

Answer 4

occlusion of the central retinal vein at the level of the lamina cribrosa or just behind

Question 5

What causes CRVO?

Answer 5

thrombosis

Question 6

What causes thrombosis?

Answer 6

Physical changes
* Arteriosclerosis of neighbouring artery * Vessel wall changes e.g. phlebitis
* Raised IOP (>30mmHg)

Blood abnormality
* High blood viscosity
* Coagulation disorders

Question 7

risk factors of CRVO

Answer 7

Age 50+ (90%)
* Hypertension
* Hyper-lipidaemia
* Diabetes
* Smoking
* Raised IOP (>30mmHg)

Question 8

Answer 8

CRVO
-tortuous dilates retinal veins ( all 4 quadrants)

-round/blot and flame haemorrhages

-CWS

-macula oedema
-disc oedema