Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Duke Elder: Finals Ophthalmology (Alice) > Central retinal artery occlusion > Flashcards

Central retinal artery occlusion Flashcards

1
Q

A patient presents with a week history of sudden loss of vision in the right eye only, mainly affected the centre of the visual field. She has no pain, no floaters or flashing lights. She wears reading glasses and has hypertension. What are 6 aspects of examination that you would perform?

A
  1. Visual acuity
  2. Pupil reflexes
  3. Slit lamp examination of anterior segment
  4. Intraocular pressure (applanation tonometry)
  5. Vitreous examination
  6. Fundal examination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is shown in the fundal photograph and what is the most likely diagnosis?

A

Dilated, tortuous retinal veins and multiple haemorrhages; central retinal artery occlusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 5 likely findings on examination in CRAO?

A
  1. reduced visual acuity in affected eye, often to finger counting
  2. RAPD in affected eye
  3. normal anterior segments and vitreous in both eyes
  4. normal IOP in both eyes
  5. pale retina, attenuation of vessels in affected eye on fundoscopy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the classical presentation of CRAO? List 3 symptoms

A
  1. Sudden (few seconds), painless loss of vision
  2. vision reduced to counting fingers (if worse, suggests ophthalmic artery may also be affected, which CRA is a branch of)
  3. may be history of amaurosis fugax preceding loss of vision in up to 10 patients
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What additional elements of examination should always be done in suspected CRAO? 4 key things

A

Systemic examination to find cause of occlusion

  1. Carotid auscultation for bruits
  2. Heart sounds for murmurs
  3. Radial pulse for atrial fibrillation
  4. Blood pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Explain the blood supply to the retina. There are 2 main sources

A
  1. Central retinal artery is branch of ophthalmic artery, which is first branch of internal carotid artery. CRA supplies blood to surface of optic disc, here is divides to two main branches: superior and inferior: these divide into temporal and nasal branches
  2. Outer retina is supplied by the choriocapillaries ofthe choroid that branches off the ciliary artery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the appearance of the retina likely to be in CRAO? 3 key things

A
  1. Pale retina with attenuation of the vessels
  2. May be sludging + segmentation of blood column in the arteries (‘cattle trucking’)
  3. Centre of macula (fovea) stands out as a cherry red spot
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why does RAPD occur in CRAO?

A

Presence of RAPD implies retinal ischaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does the presence of RAPD represent for prognosis in CRAO?

A

Greater chance of progressing to neovascularisation, with worse visual prognosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why is CRAO a serious condition in the UK?

A

Common cause of visual loss, second cause of reduced vision to retinal vascular disease after diabetic retinopathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are 4 groups of risk factors for CRAO?

A
  1. Atherosclerotic (commonest)
  2. Haematological
  3. Inflammatory
  4. Ophthalmic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the 5 atherosclerotic risk factors for CRAO?

A
  1. Hypertension
  2. Hyperlipidaemia
  3. Diabetes
  4. Smoking
  5. Obesity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are 6 haematological risk factors for CRAO?

A
  1. Protein S, protein C or antihthrombin deficiency
  2. Activated protein C resistance
  3. Factor V Leiden
  4. Myeloma
  5. Waldenstrom’s macroglobulinaemia
  6. Antiphospholipid syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are 6 inflammatory risk factors for CRAO?

A
  1. Sarcoidosis
  2. Behcet’s disease
  3. Polyarteritis nodosa
  4. Granulomatosis with polyangiitis
  5. SLE
  6. Goodpasture syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are 4 ophthalmic risk factors for CRAO?

A
  1. Glaucoma
  2. Trauma
  3. Optic disc drusen
  4. Orbital pathology
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are 6 differentials for sudden, painless loss of vision?

A
  1. Branch retinal vein occlusion (BRVO)
  2. Central retinal artery occlusion (CRAO)
  3. Wet age-related macular degeneration (wet AMD)
  4. Anterior ischaemic optic neuropathy
  5. Retinal detachment
  6. Vitreous haemorrhage
17
Q

How does the presentation of BRVO compare with CRAO?

A

Usually less severe loss of vision, may be asymptomatic, dilated retinal veins with retinal haemorrhages and cotton wool spots only in one quadrant. Commonest association is hypertension

18
Q

What is the difference in presentation between retinal detachment and CRAO?

A

Retinal detachment is usually associated with flashes are floaaters beforehand and seeing a “curtain” coming across the vision

19
Q

What is the presentation of vitreous haemorrhage like?

A

Degree of bleed determines extent of visual loss.

Small bleed = cobwebs, mild reduction in vision.

Large bleed = extensive vision loss (HM [hand movement] vision)

Commoner in proliferative diabetic retinopathy

20
Q

What are 4 urgent investigations to perform in suspected CRAO?

A
  1. Systemic examination (BP, heart sounds, auscultate carotids, radial pulse)
  2. Blood tests: FBC, ESR, glcose
  3. Fundus fluorescein angiography (FFA)
  4. Optical coherence tomography (OCT)
21
Q

What is FFA used for in suspected CRAO?

A

Differentiation between non-ischaemic or ischaemic (retinal capillary closure i.e. non-perfusion, leakage i.e. macular oedema, neovascularisation of optic disc and/or retina).

22
Q

How often does neovascularisation occur following CRAO and when is it more common?

A

Neovascularisation occurs in about 20% of eyes within 6-12 months, more commonly in eyes with greater than 10 optic disc diameters of retinal capillary non-perfusion

23
Q

What is the advantage of performing OCT in CRAO?

A

Shows retinal thickening and macular oedema

24
Q

What are 3 possible complications of CRAO?

A
  1. Cystoid macula oedema
  2. Neovascularisation of optic disc and retina
  3. Neovascular glaucoma (neovascularisation of iris and aquoeus drainage angle)
25
Q

What are 3 aspects of long-term management of CRAO?

A
  1. Medical maangement of risk factors including smoking cessation
  2. Non-ischaemic: if macula oedema, consider intravitreal steroid or intravitral anti-VEGF
  3. Ischaemic: pan-retinal laser photocoagulation (PRP); intravitreal anti-VEGF
26
Q

What is the emergency management of CRAO? Give 3 examples.

A

Attempting to reperfuse ischaemic tissue as quickly as possible

  1. if present within 90-100 minutes of symptom onset, firm ocular massage over closed lid for 10 seconds with five second interludes repeatedly
  2. Anterior chamber paracentesis with acetazolamide (also apraclonidine, mannitol, beta blockers)
  3. Dilatation of the artery e.g. sublingual isosorbide dinitrate, inhaled carbogen or hyperbaric oxygen

others being tried include oral pentoxyifyllin, intra-arterial fibrinolysis with urokinase, enhanced external counterpulsation (EECP), thrombolysis with tPA

Duke Elder: Finals Ophthalmology (Alice) (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions