5: Visual loss and blindness Flashcards Preview

Ophthalmology Week 2 2017/18 > 5: Visual loss and blindness > Flashcards

Flashcards in 5: Visual loss and blindness Deck (65)
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1
Q

What is the major artery supplying the eye?

Which artery in the neck does it stem from?

A

Ophthalmic artery

Internal carotid artery

2
Q

What are the important branches of the ophthalmic artery which you should know?

A

Central retinal artery (inner 2/3rds of retina)

Posterior ciliary arteries (optic nerve head)

3
Q

Which structure supplies the other 1/3rd of the retina?

A

Choroid

4
Q

What vascular problems cause sudden visual loss?

A

Occlusion

Haemorrhage

5
Q

Which artery supplies the inner 2/3rds of the retina?

A

Central retinal artery

6
Q

What are the symptoms of central retinal artery occlusion?

A

Sudden profound vision loss

Which is painless

7
Q

What reflex is disrupted in CRAO?

A

Pupillary light reflex

pupil doesn’t constrict in response to light - relative afferent pupil defect (go back and forth fast enough and the pupil will actually dilate in response to light)

because optic nerve is infarcted

8
Q

What does the retina look like in a central retinal artery occlusion?

A

Pale

Cherry spot fovea

Arteries either absent or blocked

9
Q

Central retinal artery occusion is a type of ___.

A

stroke

10
Q

What causes central retinal artery occlusion?

A

Carotid artery disease

11
Q

How are central retinal artery occlusions managed?

A

Ocular massage (attempt to convert to branch occlusion)

Manage risk factors

12
Q

What is amaurosis fugax?

A

Transient central artery occlusion

13
Q

What are the symptoms of amaurosis fugax?

A

Transient painless visual loss

lasting 5 mins with full recovery

14
Q

How is amaurosis fugax treated?

A

Aspirin (anti-platelet)

Urgent referral to stroke clinic

15
Q

What is Virchow’s triad?

A

Endothelial injury

Hypercoagulability

Stasis / turbulent blood flow

16
Q

What are the symptoms of central retinal vein occlusion?

A

Sudden painless visual loss

17
Q

CRVO is associated with a raised ___ pressure.

A

intraocular

18
Q

What are the signs of CRVO on fundoscopy?

A

Haemorrhages - inc. cotton wool spots

Dilated torturous veins

Optic disc and macular swelling

19
Q

What type of scan is used to pick up macular oedema?

A

OCT scan

20
Q

How is CRVO treated?

A

Laser treatment

Anti-VEGF injections (VEGF released in response to ischaemia, encourages development of poorly structured blood vessels which haemorrhage)

Address risk factors

21
Q

What processes drive

a) arterial
b) venous

occlusions of the eye?

A

a) Internal carotid disease

b) Venous stasis

22
Q

Which arteries supply the optic nerve head?

A

Posterior ciliary arteries

23
Q

What is occlusion of the posterior ciliary arteries also known as?

A

Ischaemic optic neuropathy

24
Q

What tends to cause arterial ischaemic optic neuropathy?

A

Giant cell arteritis

25
Q

What causes non-arteritic ischaemic optic neuropathy?

A

Atherosclerosis

26
Q

What does the optic disc look like in ischaemic optic neuropathy?

A

Swollen

27
Q

What is the main symptom of arteritic ischaemic optic neuropathy?

A

Sudden irreversible visual loss

28
Q

Irreversible blindness is an end-stage symptom of giant cell arteritis. What are the other symptoms?

A

Headache

Jaw claudication

Scalp tenderness

Tender, enlarged temporal arteries

Transient arterial occlusions (amaurosis fugax)

Malaise

Raised inflammatory markers

29
Q

How is giant cell arteritis treated to prevent immediate bilateral blindness?

A

High dose oral prednisolone

30
Q

Where in the eye does bleeding tend to occur?

A

Vitreous cavity

31
Q

What is a bleed into the vitreous cavity called?

A

Vitreous haemorrhage

32
Q

What are the symptoms of vitreous haemorrhage?

A

Loss of vision

Floaters

33
Q

What are signs of vitreous haemorrhage on fundoscopy?

A

Loss of red reflex

Clear haemorrhage

34
Q

How is vitreous haemorrhage managed?

A

Management of underlying disease

Vitrectomy

35
Q

What are the symptoms of retinal detachment?

A

GRADUAL painless loss of vision

Flashes

Floaters

36
Q

What is the commonest cause of blindness in elderly people?

A

Age-related macular degeneration (ARMD)

37
Q

What are the two types of ARMD?

A

Wet (sudden)

Dry (gradual)

38
Q

What causes wet ARMD?

A

New blood vessels grow in choroid, causing fluid bulge and scarring

39
Q

What are the symptoms of wet ARMD?

A

Rapid CENTRAL vision loss

Metamorphopsia - visual distortion

40
Q

How is wet ARMD treated?

A

Anti-VEGF injections

41
Q

What is the jist of glaucoma?

A

Damage to optic nerve

42
Q

What are two different types of glaucoma?

A

Open-angle

Closed-angle

43
Q

Where does aqueous fluid drain?

A

Canal of Schlemm (trabecular meshwork) at iridocorneal angle

44
Q

What causes closed-angle glaucoma?

A

Blockage of trabecular network by bulging iris causes increased IOP

45
Q

What are the symptoms of closed angle glaucoma?

A

Painful, red eye

Sudden peripheral visual loss

Headache, nausea, vomiting

46
Q

How is closed angle glaucoma treated?

A

Lower IOP with drops - carbonic anhydrase, beta blockers etc.

Laser iridotomy - trabeculectomy???

47
Q

What are some causes of gradual visual loss?

A

Cataracts

Dry ARMD

Refractive error

Glaucoma

Diabetic retinopathy

48
Q

What are cataracts?

A

Cloudiness of the lens

49
Q

Which drugs can induce cataracts?

A

Steroids

50
Q

When would cataracts be managed?

How?

A

If symptomatic

Surgical lens implant

51
Q

Dry ARMD causes (sudden / gradual) visual loss.

A

gradual visual loss

52
Q

ARMD causes (central / peripheral) vision loss.

A

central vision loss

53
Q

What causes dry ARMD?

A

Build-up of DRUSEN - waste products below retina

Causes retina to tent away from choroid and become atrophic

54
Q

How is dry ARMD treated?

A

Supportively - magnifiers, care etc.

55
Q

What is refractive error?

A

Eye cannot clearly focus an image

56
Q

What is myopia?

Which type of lens is used to treat it?

A

Short-sightedness

Light focused TOO EARLY, BEFORE RETINA

Treated using concave lens (diverges light)

57
Q

What is hypermetropia?

Which type of lens is used to treat it?

A

Long-sightedness

Light focused too LATE

Treated using convex lenses

58
Q

What is astigmatism?

A

Irregular CORNEAL curvature

59
Q

What is presbyopia?

A

Loss of accommodation reflex with aging

60
Q

What type of glaucoma causes gradual visual loss or is asymptomatic?

A

Open-angle glaucoma

61
Q

What are the signs of open-angle glaucoma?

A

Cupped disc

Visual field defects

but patient may be asymptomatic

62
Q

What is the cup:disc ratio like in glaucoma?

A

Too big

63
Q

Where does visual loss occur first in glaucoma?

A

Peripheral first

64
Q

Do patients with glaucoma have tunnel vision?

A

No - they fill in the rest of the image (incorrectly)

65
Q

How is open-angle glaucoma treated?

A

Drops to lower BP

Laser treatment

Surgery