Visual Loss and Blindness Flashcards Preview

Ophthalmology > Visual Loss and Blindness > Flashcards

Flashcards in Visual Loss and Blindness Deck (46):
1

Causes of sudden visual loss:
(3)

Vascular aetiology
Retinal detachment
Age related macular degeneration (ARMD) - wet type

2

What is the major blood supply to the eye?

Various branches of the Opthalmic Artery

3

Symptoms of Central Retinal Artery Occlusion:
(3)

Sudden visual loss
Profound (CF or less- remember CRA is ‘end artery’)
Painless

4

Signs of Central Retina Artery Occlusion:
(2)

Relative Afferent Pupil Defect

Pale oedematous retina, thread-like retinal vessels

5

Causes of central retinal artery occlusion:
(2)

Carotid artery disease

Emboli from the heart (unusual)

6

Ophthalmic management of Cental Retinal Artery Occlusion:

If patient presents within 24 hours:
Occular massage (try to convert Central Retinal Artery Occlusion to Branch Retinal Artery Occlusion)

7

Vascular management of Central Retinal Artery occlusion:

Establish source of embolus – carotid doppler
Assess and manage risk factors

8

Management of CRAO:

Ophthalmic management:
If presents within 24 hours,
Ocular massage (try to convert CRAO to BRAO)


Vascular management:
Establish source of embolus – carotid doppler
Assess and manage risk factors

9

What is Amaurosis Fugax?

Amaurosis fugax (Latin fugax meaning fleeting, Greek amaurosis meaning darkening, dark, or obscure) is a painless TEMPORARY loss of vision in one or both eyes.
("transient CRAO")

Immediate referral to TIZ clinic!

10

What is Branch Retinal Artery Occlusion?

Branch retinal artery occlusion (BRAO) is a rare retinal vascular disorder in which one of the branches of central retinal artery is obstructed

11

Symptoms of Amaurosis Fugax:

transient painless visual loss
‘like a curtain coming down’
lasts~5mins with full recovery

12

Management of Amaurosis Fugax:

Immediate referall to TIA clinic

Aspirin

13

Systemic causes of central retinal vein occlusion:

Atherosclerosis
Hypertension
Hyperviscosity
(virchow's triad)

14

Ocular causes of central retinal vein occulsion:

Raised IOP (venous stasis)

15

Causes of central retinal vein occlusion:

Systemic causes:
Atherosclerosis }
Hypertension } Virchow’s triad
Hyperviscosity }

Ocular causes:
raised IOP (venous stasis)

16

Symptoms of CRVO:

Sudden visual loss
Moderate to severe visual loss (6/9 – P of L)

17

Signs of CRVO:

Retinal haemorrhages
Dilated tortuous veins
Disc swelling and macular swelling

18

Treatment of CRVO:

Based on treatment of systemic or ocular causes (eg hypertension, diabetes, glaucoma)

Monitor : may develop complications due to development of new vessels (laser treatment may be required to avoid complications from these vessels eg vitreous haemorrhage)

More recently, anti- VEGFs used (VEGF = vascular endothelial growth factor)

19

What are anti-VEGFs?

Vascular Endothelial Growth Factor

20

Causes of sudden visual loss (vascular aetiology):

Occlusion of:
- retinal circulation
- optic nerve head circulation

Haemorrhage from:
- abnormal blood vessels (eg diabetes, wet ARMD)
- retinal tear

21

What is ischaemic optic neuropathy?

Occlusion of optic nerve head circulation

Posterior ciliary arteries (PCA) become occluded, resulting in infarction of the optic nerve head
(PCA not end arteries

(2 types - arteritic, non-arteritic)
Both cause sudden, profound visual loss with swollen disc

22

What are the two types of ischaemic optic neuropathy?

Arteritic - 50% - inflammation (GCA)
Non-arteritic -50% - atherosclerosis

23

What is the pathogenesis of Arteritic ION?

Giant cell arteritis (GCA)

Medium to large sized arteries inflamed (multinucleate giant cells)

Lumen of artery becomes occluded (posterior ciliary arteries)

Visual loss from ischaemia of optic nerve head

24

What are the visual symptoms of arteritic ION?

Sudden Visual Loss
Profound (CF - NPoL)
Irreversible Blindness

25

Management of GCA:

Refer Urgently!
(Risk of sudden complete blindness in second eye. Immediate high dose systemi steroid may prevent other eye going blind)
Can be fatal
Treatment wih high dose steroids!

26

What is a vitreous haemorrhage?

Haemorrhage in the vitreous cavity

27

Cause of haemorrhage causing sudden visual loss:

Bleeding occurs from abnormal vessels
Associated with retinal ischaemia and new vessel formation eg after retinal vein occlusion or diabetic retinopathy

Bleeding occurs from normal retinal vessels
Usually associated with a retinal tear

28

Symptoms/signs of vitreous haemorrhage:

Loss of vision
"floaters"

Loss of red reflex
May see haemorrhage on fundoscopy

29

Management of vitreous haemorrhage:

(Identify cause)
Vitrectomy for non-resolving cases

30

Symptoms of retinal detachment:

Painless loss of vision
Sudden onset of flashes/floaters (mechanical separation of sensory retina from retinal pigment epithelium)

31

Signs of retinal detachment:

May have RAPD
May see tear on ophthalmoscopy

32

Management of retinal detachment:

Usually surgical

33

What is the commonest cause of blindness in Western World in patients over 65?

Age Related Macular Degeneration (ARMD)

34

What are the 2 types of age related macular degeneration?

Dry (gradual reduction in vision)
Wet (sudden reduction in vision)

35

Which type of age related macular degeneration causes sudden reduction in vision?

Wet age related macular degeneration

36

Which type of age related macular degeneration causes gradual reduction in vision?

Dry age related macular degeneration

37

What happens in Wet ARMD?

New blood vessels grow under retina – leakage causes build up of fluid/blood and eventually scarring.

38

What are the symptoms/signs of Wet ARMD?

Rapid central visual loss
Distortion (metamorphobia)
Haemorrhage/exudate

39

Current treatment for Wet ARMD?

Anti-VEGF treatment - injected into vitreous cavity
Stops new blood vessels growing by binding to VEGF (vascular endothelial growth factor)

40

What is cataract?

Cloudiness of the lens

41

Causes of cataract:

Age-related
Congenital - intrauterine infection (importance of checking red reflex in neonates)
Traumatic
Metabolic - diabetes
Drug-induced (steroids)

42

Management of cataract (if patient is symptomatic):

Management is surgical removal with intra-ocular lens implant if patient is symptomatic

43

Symptoms/signs of ARMD:

Gradual decline in vision
Central vision "missing" (scotoma)

Drusen - build up of waste products below RPE
Atrophic patches of retina

44

Management of dry ARMD:

No cure - treatment is supportive with low vision aids e.g. magnifiers

45

What is glaucoma?

Progressive optic neuropathy

Ultimately results in optic nerve damage (and therefore, visual loss)

46

Management for open-angle glaucoma:

Aim to preserve vision (by lowering IOP) with eye drops/laser/surgery

Patients need regular monitoring in eye clinic

Patients need regular monitoring in eye clinic