Sudden vision loss

Question 1

What are the causes of sudden vision loss?

Answer 1

retinal artery/vein occlusion
virteous haemorrhage
retinal detachment
wet age related macular degeneration - haemorrhage of abnormal vessels 
haemorrhages from normal vessels - e.g. bridging a retinal tear 
optic neuritis
closed angle glaucoma
stroke

Question 2

How does a central retinal artery occlusion present?

Answer 2

painless sudden vision loss

Question 3

What are the signs of a CRAO?

Answer 3

RAPD
PALE odematous retina
thread like retinal vessels
swollen retinal ganglion cells
cherry red spot at the fovea

Question 4

What does the central retinal artery supply?

Answer 4

inner 1/3rd of the retina

Question 5

What can cause CRAO?

Answer 5

carotid artery disease

emboli from the heart

Question 6

What are the two types of CRAO?

Answer 6

branch retinal artery occlusion

amaurosis fugax

Question 7

Describe a branch retinal artery occlusion?

Answer 7

only one half of the retina becomes pale

Question 8

Describe an amaurosis fugax?

Answer 8

transient visual loss, like a curtain coming down
resolves after 5 mins
nothing abnormal on examination

Question 9

What must you do with a patient with CRAO?

Answer 9

urgently refer them to the stroke clinic

Question 10

What is a central retinal vein occlusion associated with?

Answer 10

Virchows triad

Question 11

What is the presentation of a CRVO?

Answer 11

sudden vision loss

rubeotic eye - vessels growing on the iris

Question 12

What are the signs of CRVO?

Answer 12

dark fundoscopy photo with cotton wool spots
retinal haemorrhages
dilated tortuous veins
disc swelling

Question 13

What are the characteristics of a branch CRVO?

Answer 13

loss of just part of a field of view - patient often not aware of it
may be painless and asymptomatic

Question 14

What is ischeamic optic neuropathy?

Answer 14

oclusion of the optic nerve head circulation - posterior cilliary artery

Question 15

What can cause ischeamic optic neuropathy?

Answer 15

giant cell arteritis

Question 16

What is the presentation of ischeamic optic neuropathy?

Answer 16

sudden vision loss

irreversible blindness

Question 17

What signs can be see on fundoscopy in an ischeamic optic neuropathy?

Answer 17

swollen optic disc

Question 18

What is a vitreous haemorrhage?

Answer 18

bleeding occuring from abnormal vessels (diabetic retinopathy or retinal vein occlusion causing new vessels to form) or bleeding can occur from normal vessels but theres been a tear - bridging retinal tear

Question 19

What is the presentation of a vitreous haemorrhage?

Answer 19

vision loss

floaters

Question 20

What are the signs of a vitreous haemorrhage?

Answer 20

loss of red reflex due to an unclear retina

haemorrhages

Question 21

What is the pathophysiology behind a retinal detachment?

Answer 21

the vitreous fluid starts to collapse in on itself as we age, as it does this it tears the retina

Question 22

What is the presentation of a retinal detachment?

Answer 22

painless loss of vision

sudden onset floaters and flashing lights (due to mechanical seperation of sensory retina from pigment epithelium)

Question 23

What are the signs of a retinal detachment?

Answer 23

RAPD

tear on ophthalmoscopy