Brainscape's Knowledge GenomeTM

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


See full index

Ophthalmology > Acute loss of vision | > Flashcards

Acute loss of vision | Flashcards

1
Q

In a patient with ALOV, what would be a helpful way of starting the history and why?

A

Ask them about previous ocular history first rather than the current presenting complaint as they might be very anxious

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

What would you ask in the history of someone presenting with ALOV (7)?

A
  1. Previous ocular history
  2. CVD
    - common cause of eye problems
  3. Family history
  4. Drugs
  5. Eye drops (contain strong drugs)
  6. Symptoms
  7. Duration/recovery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What can you specifically ask about symptoms in a history of a patient with ALOV (6)?

A
  1. Monocular and/or binocular
  2. Time of event, method of symptom awareness
    i. e. what were you doing when you noticed it? e.g. sitting watching tv, waking up, accidentally covered one eye?
  3. Change in symptoms and how long did it take to change, what helped as it got better (i.e. gradual or sudden)
  4. Associated symptoms e.g. flashes, floaters, numbness, feeling dizzy
  5. Duration/recovery
  6. Nature of visual loss
    - general, central and associated field, peripheral only, global effect on function (bump into objects, fall down steps, can’t read)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

If the patient says that they noticed their LOV by accidentally covering one eye, what does this mean about the timing of the event?

A

May not be acute, it might be gradual but they did not notice

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

What 6 examinations do you need to do for ALOV?

A
  1. VA in both eyes
  2. Visual field loss
    - central only
    - perpheral and central
    - altitudinal
    - hemianopia
  3. Pupil reactions
    - APD
  4. Anterior segment
  5. Red reflex - can you see to the back of the eye?
  6. Fundoscopy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are 6 monocular causes of ALOV? (think anatomically from front of eye to back)

A
  1. Acute corneal disease
  2. Acute chamber haemorrhage
  3. Acute cataract
  4. Vitreous haemorrhage
  5. Optic nerve
  6. Retina
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are 4 features of acute corneal disease in the cause of monocular ALOV?

A
  1. Rare to be painless
  2. Painless with HSV as it renders it anaesthetic
  3. Central cloudy cornea leading to visual loss
  4. Can come on quickly over 1 day
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are 2 features of anterior chamber haemorrhage in the cause of monocular ALOV?

A
  1. Rare for acute painless things occurrng in anterior chamber
  2. Can be caused by uveitis glaucoma haemorrhage - spontaneous anterior chamber haemorrhage so vison goes blurry (rare)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are features of acute cataract in the cause of monocular ALOV?

A

Can occur as quickly as overnight/over a week

e.g. when struck by lightening, or when capsule of lens becomes porous to fluid and becomes opalescent

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

What are 2 clinical features of vitreous haemorrhage the cause of monocular ALOV?

What can cause vitreous haemorrhages?

A
  1. Less rare
  2. Causes acute LOV, and if it is a dense vitreous haemorrhage it will cause substantial visual loss

Caused by proliferative diabetic retinopathy, retinal tear, posterior vitreous detachment

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

What are 3 optic nerve causes of monocular ALOV?

A
  1. Optic neuritis - can range from NPL to vaguely blury
  2. Ischaemic optic neuropathy - acute cessation of blood supply to optic nerve
    - When only half of optic nerve is affected, can lead to an altitudinal field defect (loss of inferior or superior field of vision, which does not cross the horizontal plane)
  3. Check for cranial arteritis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the 3 signs and symptoms of cranial arteritis?

A
  1. Acute visual loss
  2. Over age of 60
  3. Associated with headache, pain on chewing/combing hair
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What 2 investigations must you do for cranial arteritis and who would you refer to?

A
  1. Raised ESR

2. Referral to ophthalmologist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 6 retinal monocular causes of ALOV?

A
  1. Branch retinal vein occulsion
  2. Branch retinal artery occlusion
  3. Central retinal vein occlusion
  4. Central retinal artery occlusion
  5. Retinal detachment
  6. Macular haemorrhage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 3 binocular global causes of ALOV according to anatomical region (front to back)?

A
  1. Chiasm
    - pituitary apoplexy
  2. Optic nerve
    - infiltrative, severe papilloedema (IIH)
    - Optic neuritis
  3. Cortex (brain)
    - migraine (temporary visual field loss in zig zag pattern)
    - CVA (patterns of field loss)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 4 clinical features of pituitary apoplexy?

A
  1. Rapidly expanding pituitary tumour
  2. Bilateral, acute visual loss
  3. Eyes seem ok but have bilateral pupil afferent defect
  4. Can be painless
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What visual field loss would a stroke to the occipital cortex cause?

A

Homonymous hemaniopia (visual field defect on one side in each eye)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What visual field loss would a lesion to the optic nerve cause?

A

LOV in one eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What visual field loss would a lesion to the optic chiasm cause (2)?

A
  1. Can be total LOV in both eyes

2. Bitemporal hemaniopia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What visual field loss would a lesion behind the optic chiasm cause?

A

Field defect is more homonymous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the primary care pathway structure for common retinal causes of monocular APVL?

A

(HEIR)

  • History
  • Examination
  • Investigations/acute treatment
  • Referral
22
Q

What are the features of the HEIR formula for branch retinal vein occlusion (BVO) as a cause of monocular APVL?

A

H - on waking, central blur (involves macula) - variable
E - nil except retinal signs (check other eye for asymptomatic BVO)
I - BP (HTN), bloods (FBC, ESR, glucose)
R - Routine to out patient department (not acute)

23
Q

What are 4 causes of BVO?

A
  1. HTN
  2. Diabetes
  3. Hyperlipidaemia
  4. Systemic inflammatory disorders
24
Q

What is the pathophysiology of a BVO?

A
  • Occurs due to occlusion of a smaller branch of the retinal vein, by thrombosis.
  • They often occur at arterio-venous crossings—an intersection between a retinal artery and vein.
  • These vessels share a common sheath (connective tissue), so when the artery loses flexibility, as with atherosclerosis (hardening of the arteries), the vein is compressed
  • The narrowed vein experiences turbulent blood flow that promotes clotting, leading to a blockage or occlusion.
  • This obstruction blocks blood drainage and may lead to fluid leakage in the center of vision (macular oedema) and ischaemia—poor perfusion (flow) in the blood vessels supplying the macula
25
Q

What signs can be seen on fundoscopy with a BVO (3)?

A
  1. Haemorrhages
  2. Cotton wool spots
  3. Limited to one section of retina (drained by that vein)
26
Q

What is the prognosis of BVO?

  1. Mild occlusion
  2. Severe occlusion
A
  1. Can get spontaneous resolution as the retina opens new venous channels/shunts
  2. Prognosis for sight is poor and likely to have abnormal new blood vessels forming in areas adjacent to vein occlusion which are fragile and can bleed into the vitreous
27
Q

What are the features of the HEIR formula for central retinal vein occlusion (CRVO) as a cause of monocular APVL?

A

H - on waking, global - variable (can be only central vision blurred in mild cases)
E - acuity variable from 6/6 to CF, may have RAPD if severe, variable retinal signs, check other eye for disc exam (CRVO can be caused by raised IOP)
I - BP, bloods, IOP
R - Eye casualty (new treatments in early stages, monitoring for complications)

28
Q

What are 5 causes of CRVO?

A
  1. Raised IOP
  2. HTN
  3. Diabetes
  4. Hyperlipidaemia
  5. Systemic inflammatory disorders
29
Q

What 5 signs can be seen on fundoscopy in CRVO?

A
  1. Disc oedema
  2. Increased dilatation and tortuosity of all retinal veins
  3. Widespread deep and superficial haemorrhages (blood and thunder fundus)
  4. Cotton wool spots
  5. Retinal oedema and capillary non-perfusion in all four quadrants of the retina.
30
Q

What determines the vision affected in CRVO?

A

The level of macular oedema secondary to blocked vein

31
Q

What are 2 complications of CRVO?

A
  1. Permanent severe visual loss

2. Rubeotic glaucoma (new bv on iris) - if untreated leads to blindness

32
Q

What are the features of the HEIR formula for central retinal artery occlusion (CRAO) as a cause of monocular APVL?

A

H - Intermittent prodromal phase - shutter effect

E - Acuity CF to NPL,
pupils - APD (if NPL)/RAPD.
Signs - retinal oedema, cherry red spot, emboli, carotid bruits

I/T - Primary care I = BP/nil, T = rebreathe into paper bag and ocular massage. Secondary care I = ESR, carotid US, cardiac echo, T = rebreathe and ocular massage, acetazolamide, paracentesis

R - eye casualty

33
Q

What are 4 causes of CRAO?

A
  1. HTN
  2. Carotid artery atherosclerosis
  3. Giant cell arteritis
  4. Dissecting aneurysms
34
Q

How does rebreathing into a paper (not plastic) bag help someone with CRAO?
How does ocular massage help?

A

Raised PCO2, dilate bv, causing embolus to pass on

Massage - press aq out of eye acutely and release, to suddenly lower IOP, releasing embolus

35
Q

Why is it important to do an ESR first, as well as carotid US when you suspect CRAO?

A

raised ESR is a sign of cranial arteritis

36
Q

Why is acetazolamide given in CRAO?

A

To lower IOP

37
Q

Why is paracentesis done for CRAO?

A

Needle into anterior chamber to suddenly lower IOP to cause embolus to move out

38
Q

If cranial arteritis is suspected, what treatment is given?

A

High dose steroids to reduce inflammation

39
Q

How urgently do you need to refer to eye casualty in CRAO?

A

Urgently - retina dies in 12 hours if it is devoid of blood so refer quickly to save vision

40
Q

Why do you see the cherry red spot?

A

Retina is thinner at fovea so you can see choroid (red) where the surrounding retina is opalescent as it is oedematous and reflects light

41
Q

Why are retinal arterioles thin in CRAO?

A

They are not carrying any blood

42
Q

What are the features of the HEIR formula for branch retinal artery occlusion (BRAO) as a cause of monocular APVL?

A

H - comes on anytime - can be sectoral (patchy) +/- central

E - Acuity 6/5 to CF
May have RAPD,
Carotid bruits, field defect, fundoscopy - embolus, signs of hypertensive retinopathy (e.g. AV nipping, flame haemorrhages, cotton wool spots)

I - BP, carotid US, bloods, cardiac echo

R - Eye casualty for confirmation and onward referral for investigations and treatment

43
Q

How urgently do patients with suspected BRAO or ALOV from arterial causes need to be seen? WHo do they need to be referred onwards to?

A

Urgently to eye casualty as they are at risk of a stroke

Refer to TIA clinic

44
Q

What are the features of the HEIR formula for retinal detachment/vitreous haemorrhage as a cause of monocular APVL?

A

H - floaters +/- flashes, +/- field loss (may not noticed until macula affected)
E - Acuity normal if macula on/if severe, can have severe VA defect, field loss pattern, RAPD if extensive, red reflex abnormality, fundoscopy
I - Nil in primary care
R - Eye casualty

45
Q

How are retinal detachment and vitreous haemorrhage related?

A

Vitreous haemorrhage often precedes retinal detachment

46
Q

How urgently do you need to refer a patient with retinal detachment/vitreous haemorrhage to eye casualty?

A

Urgently to preserve vision

47
Q

What is the pathology of retinal detachment/vitreous haemorrhage (4)?

A
  1. Due to ageing process, in short-sighted eyes
  2. With age, vitreous becomes degenerate - it breaks up into pockets of fluid which coalesce. Eventually, the vitreous detaches from retina at posterior part of eye
  3. However vitreous is well attached to anterior part of eye 360 degrees and does not detach from that
  4. This causes the vitreous to collapse forwards and downwards which can bring tissue from optic nerve head, causing floaters. Detachment may also cause the rupture of a bv, causing vitreous haemorrhage.
48
Q

What is the prognosis of retinal detachment/vitreous haemorrhage (3)?

A
  1. Can be benign, floaters settle down, but can persist. It is not a threat
  2. However, an abnormal vitreous attachment to a weak area of retina can cause retina tears, so fluid from vitreous can go through the tear and peel off the retina. Retina detachment leads to visual field defects.
  3. Can occur very quickly, especially in the superior retina due to gravity. If it occurs in the inferior retina, it can take a very long time, so patients only present when central retina is affected
49
Q

What are the features of the HEIR formula for macular haemorrhage as a cause of monocular APVL?

A

H - Distortion, positive scotoma (black blob in vision)

E - Acuity variable, no RAPD, full peripheral field, central haemorrhage on fundoscopy and signs of primary disease (e.g. DR)

I - BP

R - Eye casualty

50
Q

What are the main 4 causes of macular haemorrhage?

A
  1. AMD
  2. Diabetic retinopathy
  3. Macroanneurysm (dilated retinal artery that bleeds)
  4. HTN
51
Q

Why is there no RAPD with macular haemorrhage?

A

Disease only involving only central retinal will not affect pupil reaction as there are other parts of retina that can fire

Ophthalmology (12 decks)

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