Vascular Causes of Sudden Visual Loss

Question 1

what is the major blood supply to the eye

Answer 1

various branches of the ophthalmic artery

Question 2

what are the 2 different vascular aetiologies of sudden visual loss

Answer 2

occlusion or haemorrhage

Question 3

what can be occluded to result in sudden visual loss

Answer 3

occlusion of retinal artery or vein, or occlusion of optic nerve circulation

Question 4

what can haemorrhage come from, resulting in sudden visual loss

Answer 4

haemorrhage from abnormal blood vessels or from normal blood vessels

Question 5

what symptoms are associated with central retinal artery occlusion(CRAO)

Answer 5

sudden visual loss, painless

Question 6

what signs are associated with central retinal artery occlusion(CRAO)

Answer 6

RAPD(relative afferent pupil defect), pale oedematous retina and thread-like retinal vessels

Question 7

what are the causes of CRAO

Answer 7

carotid artery disease, emboli from the heart(unusual)

Question 8

what are 2 other variants of retinal artery occlusion, other than CRAO

Answer 8

branch retinal artery occlusion, Amaurosis fugax(aka transient CRAO)

Question 9

what symptoms and signs are associated with amaurosis fugax(transient CRAO)

Answer 9

transient painless visual loss, ‘like a curtain coming down’, lasts ~5mins with full recovery
usually no signs
(refer to stroke clinic)

Question 10

what factors are associated with the formation of a central retinal vein occlusion

Answer 10

endothelial damage(ag diabetes), hypercoagulability(eg cancer), abnormal blood flow(eg hypertension)

Question 11

what signs symptoms are associated with central/branch retinal vein occlusion

Answer 11

symptoms = sudden visual loss
signs = retinal haemorrhages, dilated tortuous veins, disc and macular swelling,

Question 12

what is occluded in optic nerve head circulation occlusion and what does this lead to

Answer 12

posterior ciliary arteries become occluded, results in infarction of optic nerve head

Question 13

what signs and symptoms are seen in ischaemic optic neuropathy

Answer 13

symptoms = sudden visual loss, usually painless
signs = pale and swollen optic nerve

Question 14

what is optic nerve head occlusion also called

Answer 14

ischaemic optic neuropathy(ION)

Question 15

what is an inflammatory condition that can cause ischaemic optic neuropathy(ION)

Answer 15

temporal(giant cell) arteritis

Question 16

describe how the posterior ciliary arteries are affected in temporal arteritis

Answer 16

wall becomes so inflamed and thickened that lumen is occluded

Question 17

what signs are seen in temporal(giant cell) arteritis

Answer 17

headache, scalp tenderness, enlarged temporal artery

can be sight and life threatening

Question 18

describe how bleeding can occur from abnormal blood vessels causing vitreous haemorrhage

Answer 18

retinal ischaemia in diabetes or retinal vein occlusion causes abnormal, fragile new blood vessel formation

Question 19

give an example of how bleeding can occur from abnormal blood vessels causing vitreous haemorrhage

Answer 19

when bridging a retinal tear

Question 20

what are the signs and symptoms of a vitreous haemorrhage

Answer 20

signs = loss of red reflex, may see haemorrhage on fundoscopy
symptoms = loss of vision, 'floaters'

Question 21

describe what happens in rhegmatogenous retinal detachment

Answer 21

mechanical separation of sensory retina from retinal pigment epithelium

Question 22

what signs and symptoms are seen in retinal detachment

Answer 22

painless visual loss, sudden onset flashers/floaters, may have RAPD, mat see tear on fundoscopy

Question 23

what is the commonest cause of blindness in the UK, and what are the 2 different types

Answer 23

age related macular degeneration(AMRD)

types = wet AMRD (sudden visual loss) and dry AMRD(gradual visual loss

Question 24

describe the mechanism behind wet AMRD

Answer 24

new blood vessel growth under the retina, leakage causes build up of fluid/blood and eventually scarring

Question 25

what signs and symptoms are associated with wet AMRD

Answer 25

signs = haemorrhage/exudate
symptoms = rapid central visual loss, distortion(metamorphopsia)