Sudden Painless Loss of Vision 2

Question 1

What are causes/RF of CRVO?

Answer 1

Arteriosclerosis
Hypertension
DM
Polycythmia
Glaucoma

Question 2

Describe visual loss in CRVO. Mechanism?

Answer 2

Less sudden then CRAO
If whole vein is occluded - visual loss in acuity

Mechanism is development of ischaemia and macular oedema

Question 3

CRVO vs BRVO?

Answer 3

CRVO is at the level of the optic nerve and is never asymptomatic

BRVO has visual deficit corresponding to area of occlusion

Question 4

What are types of CRVO? Describe?

Answer 4

Ischaemic:
Cotton wool spots - ischaemic optic nerve fibres
Swollen optic nerve
Macular oedema
Risk of neovascularisation

Non-ischaemic:
Better acuity and prognosis
Can convert to ischaemic form

Question 5

What is Ix and Mx for CRVO?

Answer 5

Refer
Fundus photography
Fluorescein angiography
Lasar photocoagulation if retinal neovascularisation
Anti-VEGF - bevacizumab, ranibizumab
Aim to prevent rubeotic glaucoma
Dexamethasone, intravitreal implants

Question 6

What are causes of vitreous haemorrhage? CF?

Answer 6

Proliferative retinopathy
CRVO
BRVO
ARMD
Retinal tear
Retinal detachment
Trauma

CF:
small black dots
sudden painless visual loss
no red reflex

Question 7

What investigation in vitreous haemorrhage

Answer 7

Fundoscopy
If fundus cannot be visualised -

UltraSound B-scan to identigy a cause

Question 8

Mx for vitreous haemorrhage

Answer 8

Spontneous absorption

Vitrectomy if dense or retinal torn/detached or photocoagulation for neovascularisation is required

Question 9

DDx of sudden painless loss of vision

Answer 9

Anterior ischaemic optic neuropathy
CRAO
CRVO
Retinal detachment
Vitreous haemorrhage