Sudden loss of vision

Question 1

causes of sudden loss of vision

Answer 1

optic neuritis, retinal artery occlusion, anterior ischaemic optic neuropathy (GCA), vitreous haemorrhage, transient visual loss, retinal detachment, acute closed angle glaucoma, migraine

Question 2

what is anterior ischaemic optic neuropathy

Answer 2

optic nerve is damaged. post ciliary arteries blocked by inflammation or atheroma

Question 3

what is seen on fundoscopy AION

Answer 3

pale swollen optic disc

Question 4

what is the cause of arteritic AION

Answer 4

GCA: other eye at risk until steroids given. malaise, jaw claudification, tender scalp, temporal arteries and neck pain

Question 5

tests in GCA

Answer 5

high ESR, high CRP

Question 6

treatment GCA

Answer 6

prednisolone 80mg /24h

Question 7

associations non arteritic AION

Answer 7

incr bp, incr lipids, DM, smoking.

Question 8

what is vitreous haemorrhage due to

Answer 8

retinal new vessels, retinal tears, retinal detachment, trauma

Question 9

what are vitreous floaters

Answer 9

small extravasations of blood- small black dots or ring like forms

Question 10

treatment vitreous haemorrhage

Answer 10

spontaneous- absorption. dense VH- vitrectomy

Question 11

what happens in optic neuritis

Answer 11

unilateral loss of acuity over hours-days. colour vision affected- red desaturation. eye movements hurt.

Question 12

what does the pupil show in optic neuritis

Answer 12

afferent defect- absent direct response but consensual response is present

Question 13

disc appearance in optic neuritis

Answer 13

normal in 60%; swollen, blurred, hyperaemic, temporal pallor

Question 14

what does temporal pallor suggest in optic neuritis

Answer 14

past attack of optic neuritis in the same eye

Question 15

how long does recovery take optic neuritis

Answer 15

2-6 weeks. 45-80% develop MS.

Question 16

causes optic neuritis

Answer 16

MS, syphilis, Lebers optic atrophy, diabetes, vitamin deficiency,

Question 17

treatment optic neuritis

Answer 17

high dose methylprednisolone, then prednisolone

Question 18

what should you think if the vision loss is transient

Answer 18

vascular cause

Question 19

typical causes transient vision loss

Answer 19

vascular, TIA, migraine, MS, subacute glaucoma, papilloedema

Question 20

how soon is the visual loss in central retinal artery occlusion

Answer 20

within seconds of occlusion. afferent pupil defect within seconds

Question 21

appearance of retina in central retinal artery occlusion

Answer 21

white with cherry red spot at the macula

Question 22

what happens to acuity in central retinal artery occlusion

Answer 22

decreases

Question 23

what is the occlusion due to in central retinal artery occlusion

Answer 23

usually thromboembolic- signs of atherosclerosis, bruits, incr BP, heart disease, diabetes

Question 24

treatment central retinal artery occlusion

Answer 24

if seen within 6h aim is to increase retinal blood flow by reducing IOP- ocular massage, surgical removal aqueous from ant chamber or use of antihypertensives

Question 25

what happens if a single branch of the retinal artery is occluded

Answer 25

retinal and visual changes relate only to the part of retina supplied

Question 26

which is commoner- central retinal vein or artery occlusion

Answer 26

retinal vein

Question 27

associations central retinal vein occlusion

Answer 27

arteriosclerosis, incr BP, diabetes and polycythaemia, glaucoma (all types)

Question 28

which visual loss is more sudden retinal vein or artery

Answer 28

artery

Question 29

what is visual loss due to in central retinal vein occlusion

Answer 29

ischaemia and macular oedema

Question 30

what is central retinal vein occlusion divided into

Answer 30

non ischaemic- better acuity and prognosis, less dramatic signs; and ischaemic

Question 31

what is used to see degree of ischaemia central retinal vein occlusion

Answer 31

fundus fluorescin angiogram

Question 32

signs on fundoscopy central retinal vein occlusion ischaemic

Answer 32

cotton wool spots, swollen optic nerve, macular oedema, risk of neovascularisation)

Question 33

treatment central retinal vein occlusion

Answer 33

bevacizumab, lasers, dexamethasone intravitreal implants

Question 34

branch retinal vein occlusion signs

Answer 34

unilateral visual loss, fundal appearances in the corresponding area

Question 35

what does retinal ischaemia lead to

Answer 35

release VEGF (vascular endothelial growth factor) and retinal new vessel formation

Question 36

how to treat neovascularisation

Answer 36

laser photocoagulation

Question 37

how does the retinal vein occlusion look under fundoscopy

Answer 37

hyperaemia, haemorrhages- stormy sunset

Question 38

other causes sudden visual loss

Answer 38

retinal detachment, acute glaucoma, migraine

Question 39

is sudden bilat visual loss usual

Answer 39

no- suspect CMV retinitis in HIV patient

Question 40

what type of eyes are more prone to retinal detachment

Answer 40

myopic

Question 41

what happens in retinal detachment

Answer 41

holes/tears in retina allow fluid to separate sensory retina from retinal pigment epithelium

Question 42

what does retinal detachment present with

Answer 42

4 F's- floaters, flashes, field loss, fall in acuity

Question 43

what can retinal detachment be due to

Answer 43

rhegmatogenous, 2ary to intraocular problem- melanoma, diabetes; after cataract surgery, trauma

Question 44

if there is a superior detachment where is the field loss

Answer 44

inferior

Question 45

treatment retinal detachment

Answer 45

vitrectomy and gas tamponade, scleral silicone implants