Ophthalmology - Loss of Vision Flashcards
(119 cards)
1
Q
Do cataracts cause sudden or gradual loss of vision?
A
Gradual
2
Q
What are cataracts?
A
The lens in the eye becomes cloudy and opaque due to denatured protein.
3
Q
What is the job of the lens?
A
Job of lens is to focus light coming onto the eye at the retina at the back of the eye.
4
Q
What % of >65s have evidence of cataracts?
A
75%
5
Q
Describe the vision loss in cataracts
A
- Very slow reduction in vision
- Progressive blurring/clouding of vision
- Difficulties due to glare from bright lights (‘starbursts’) – ‘haloes’ around lights
6
Q
What condition may ‘haloes’ around lights indicate?
A
Cataracts or glaucoma
7
Q
What may patients who see ‘haloes’ around lights complain of?
A
May complain of difficulty driving at night
8
Q
Cataracts can rarely present in children. How may they be picked up in children?
A
- May simply present as a squint
- May be an incidental finding of leukocoria (reflection of white light)
9
Q
What is leukocoria?
A
Leukocoria means “white pupil’ and it refers to the reflection of white light seen upon direct illumination of the fundus through the pupil, in contrast to the usual red glow.
10
Q
How can cataracts be screened for during the neonatal exam?
A
Can be screened for using the red reflex during neonatal examination
11
Q
Risk factors for cataracts?
A
- Age
- Smoking
- Diabetes
- Alcohol
- Sunlight exposure
- Corticosteroid use
- Trauma
- Previous eye surgery
12
Q
What is the management for cataracts?
A
Surgery
13
Q
What does cataracts surgery involve?
A
- Removing the lens that has developed a cataract and replacing it with an artificial lens (pseudophakia)
- Done using US waves (phacoemulsification) → done under topical anaesthetic
14
Q
What is glaucoma?
A
Glaucoma refers to the optic nerve damage that is caused by a significant rise in intraocular pressure. This rise in IOP is caused by a blockage in aqueous humour trying to escape the eye.
15
Q
What are the 2 types of glaucoma?
A
- Open angle
- Closed angle
16
Q
Do chronic open angle glaucoma present with sudden or gradual vision loss?
A
Gradual
17
Q
What is chronic open angle glaucioma?
A
Chronic open angle glaucoma refers to optic neuropathy with death of optic nerve fibres, with or without raised IOP.
18
Q
What aspect of the vision is affected in chronic open angle glaucoma?
A
- Affects peripheral vision first until ‘tunnel vision’ is eventually experienced
- Patient may complain of knocking into objects or having to dodge cars when crossing roads
19
Q
Give some other symptoms of chronic open angle glaucoma
A
Gradual onset of fluctuating pain, headaches, blurred vision and halos around lights (particularly at nighttime)
20
Q
What may be seen in fundoscopy in chronic open angle glaucoma?
A
Optic disc cupping
21
Q
What is optic disc cupping?
A
Optic disc cupping refers to the cup appearing to become larger over time, often due to fibres in the optic nerve dying. As the structural support for the optic disc is no longer there, the cup seems larger.
22
Q
Which investigation is used to measure the intraocular pressure?
A
Tonometry
23
Q
What will be seen in a visual field assessment in glaucoma?
A
Peripheral vision loss
24
Q
What are the 4 pharmacological agents used in chronic open angle glaucoma?
A
- Topical beta blocker e.g. timolol → reduce aqueous production
- Prostaglandin analogue eye drops e.g. latanoprost → increase uveoscleral outflow
- Carbonic anhydrase inhibitors (e.g. Dorzolamide) → reduce aqueous production
- Miotics (e.g. pilocarpine) → increase uveoscleral outflow
25
What is the function of topical beta blockers in glaucoma?
reduce aqueous production
26
What is the function of prostaglandin analogue eye drops in glaucoma?
Increase uveoscleral outflow
27
Give an example of a prostaglandin analogue eye drop
Latanoprost
28
Give an example of a topical beta blocker
Timolol
29
What is the function of carbonic anhydrase inhibitors in glaucoma?
Reduce aqueous production
30
What is the function of miotics in glaucoma?
Increase uveoscleral outflow
31
Give an example of a miotic used in glaucoma
Pilocarpine
32
Give an example of a c**arbonic anhydrase inhibitor** used in glaucoma
Dorzolamide
33
What are the 2 main complications of glaucoma?
1. Optic neuropathy
2. Optic atrophy
34
What is optic atrophy?
Optic atrophy refers to **the death of the retinal ganglion cell axons that comprise the optic nerve with the resulting picture of a pale optic nerve on fundoscopy**.
35
How would optic atrophy present on fundoscopy?
A pale optic nerve/disc
36
How would optic atrophy affect vision?
irreversible loss of visual acuity
37
What is the most common cause of blindness in the UK?
Age related macular degeneration (ARMD)
38
What is ARMD?
Degeneration in the **macula** that causes a progressive deterioration in vision.
39
What is the macula?
Part of the retina at the back of the eye that is responsible for **central** vision, most of colour vision and the fine detail of what we see. The macula has a very high concentration of **photoreceptor** cells – the cells that detect light.
40
What are the 2 types of ARMD?
1. **Wet** (10% cases) → worse prognosis
2. **Dry** (90% cases)
41
Risk factors for ARMD?
* Age
* Smoking
* White or Chinese ethnicity
* FH
* CVS disease
42
Does ARMD present with a gradual or sudden loss of vision?
Gradual
43
Describe the vision loss in **dry** ARMD
* Progressive, gradual loss of **central vision** over **_years/decades_**
* Typically complain of **difficulty reading text**, **recognising** faces and problems with **vision in dim light** – reduced visual acuity
* **Visual fluctuation** is classic presentation – day by day vision may appear to deteriorate and improve unpredictably
44
What is seen in fundoscopy in dry ARMD?
Drusen
45
What are drusen? Are they normal?
Drusen are small, yellowish deposits of cellular debris (protein + lipids) that accumulate under the retina
* Small drusen are normal
* **Larger** and **greater** **numbers** of drusen can be an early sign of macular degeneration (common to both wet and dry)
46
Describe the vision loss in **wet** ARMD
* Progressive loss of **central vision** over **_months_**
* Visual fluctuation
* Difficulty reading text, recognising faces and seeing in dim light
47
What is seen in fundoscopy in wet ARMD?
* Drusen
* **Macular** **oedema**
48
What is a scotoma?
a central patch of vision loss
49
Results of a snellen chart investigation in ARMD?
reduced visual acuity due to degeneration of macula (& photoreceptors)
50
Management of **dry** ARMD?
* Stop smoking
* Control blood pressure
* Vitamins
51
What pharmacological agent can be used in the management of **wet** ARMD?
Anti-VEGF medications e.g. ranibizumab, bevacizumab, pegaptanib
52
What are anti-VEGF medications?
Anti-VEGF treatments are a group of medicines which reduce new blood vessel growth (**neovascularisation**) or **oedema**.
53
What is hypermetropia/hyperopia?
**Long**-**sightedness** i.e. distant objects are seen clearly but near objects appear blurred.
54
What is the cause of hypermetropia?
Eyeball is too **short,** or cornea is too **flat.** Light is focused **behind** (instead of on) the retina due to insufficient accommodation by the lens.
55
How may hypermetropia present?
* Squint (strabismus)
* Amblyopia (lazy eye) – if hypermetropia present from young age
56
If hypermetropia present from young age, what can it cause?
Amblyopia (lazy eye)
57
What is hyopia?
**Short**-**sightedness** i.e. can see objects near to you clearly but objects farther away are blurry.
58
What is the cause of myopia?
Eyeball is too **_long,**_ or cornea is too _**curved_.** Shape of eye causes light to be refracted incorrectly, focusing images **in front** of your retina instead of on your retina.
59
How is light focused in hypermetropia?
Behind the retina
60
How is light focused in myopia?
In front of the retina
61
Complications of myopia?
* Retinal detachment
* Cataracts
* Open angle glaucoma
* Posterior vitreous detachment
62
Is myopia generally diagnosed in children or adults?
Children
63
What is presbyopia?
Gradual loss of eye’s ability to focus on near objects.
64
What is the cause of presbyopia?
Hardening of lens which occurs with **ageing**. Lens becomes **less** **flexible** so cannot change shape to focus on **_close-up images,_** so they appear out of focus.
65
What are the 4 important questions to ask in **acute** vision loss?
1. What is the time course?
2. What are the associated symptoms?
3. What is the medical history?
4. What does the retina look like?
66
Give some **painless** causes of acute/subacute vision loss
* Retinal detachment
* Giant cell arteritis
* Amaurosis fugax – this is only transient
* Stroke affecting visual pathways
* Retinal vein or artery occlusion
* Vitreous haemorrhage
* Posterior vitreous detachment
* Wet age-related macular degeneration
67
Give some **painful** causes of acute/subacute vision loss
* Acute angle closure glaucoma
* Optic neuritis
* Uveitis
* Keratitis
* Endophthalmitis
68
Give 3 causes of **transient** vision loss (lasts \<24 hours)
* Migraine
* Amaurosis fugax
* Papilloedema
69
Describe the vision loss in a migraine
* Marching, sparkling, shimmering lights
* \<60 minutes
* **Both eyes** but typically only one **hemifield**
70
What is amaurosis fugax?
'**Transient darkening**' and it is used to describe a **temporary** loss of vision through **one** eye, which returns to **normal** afterwards.
Cause → This is usually due to a temporary disturbance of the **blood flow** to the back of the eye.
71
How does a papilloedema affect vision?
* **Complete** **brief** loss of vision
* May be unilateral or bilateral
72
Give some causes of a **persistent** loss of vision (\>24 hours)
* **Cataract**
* **Refractive error**
* **Dry age-related macular degeneration (AMD)**
* **Open-angle glaucoma**
* **Tumours affecting visual pathway**
* **Nutritional optic neuropathy**
73
What is giant cell arteritis/temporal arteritis?
Most common form of arteritic anterior ischaemic optic neuropathy. Systemic **vasculitis** of the medium and large arteries (i.e. inflammation of arteries).
74
Who does giant cell arteritis typically affect?
Typically elderly female
75
Describe the vision loss seen in giant cell arteritis
**_Sudden onset_ _painless_ _loss of vision_** with **headache**, **jaw** **claudication** and **scalp** **tenderness**
76
What other symptoms are seen in giant cell arteritis?
**Headache**, **jaw claudication** and **scalp** **tenderness**
77
What condition is giant cell arteritis strongly associated with?
Polymyalgia rheumatica
78
What is polymyalgia rheumatica?
Polymyalgia rheumatica is **an inflammatory disorder t**hat causes **muscle pain and stiffness, especially in the shoulders and hips**. Signs and symptoms usually begin quickly and are worse in the morning.
79
What is the management of giant cell arteritis?
High dose steroids → prednisolone
80
What occurs in retinal detachment?
Where the retina separates from the **choroid** underneath.
81
What is the cause of retinal detachment?
Usually due to a **retinal** **tear** that allows **vitreous** **fluid** to get under the retina and fill the space between the retina and choroid.
82
What are the risk factors for retinal detachment?
* Posterior vitreous detachment
* Diabetic retinopathy
* Trauma
* Retinal malignancy
* Older age
* FH
83
Describe the vision loss in retinal detachment
**_Painless_ _sudden_ loss of vision**
84
how would a patient typically describe their vision loss in retinal detachment?
**_Flashes and floaters’**_ followed by a ‘_**curtain falling over’_** their vision
85
Retinal detachment fundoscopy:
86
How does the presentation of retinal detachment differ from amaurosis fugax?
Amaurosis fugax is **transient**
87
Management of retinal detachment?
* Laser therapy
* Cryotherapy
88
What causes amaurosis fugax?
Lack of blood supply to retina e.g. plaque or blood clot in **carotid** artery.
89
Risk factors for amaurosis fugax
* PMH of heart disease
* HTN
* High cholesterol
* Smoking
* Alcohol
* Cocaine abuse
90
Describe the vision loss in amaurosis fugax
* **Painless sudden loss of vision** (one or both eyes)
* TEMPORARY
91
What occurs in posterior vitreous detachment?
Vitreous gel within the eye **separates** from the retina. This gel is important in maintaining the **structure** of the eyeball and keeping the retina pressed on the choroid.
92
Who is posterior vitreous detachment common in?
Older patients
93
Give some causes of posterior vitreous detachment
* Eye trauma
* Old age (normal part of aging)
* **Severe myopia** – also known as nearsightedness
94
Describe the presentation of posterior vitreous detachment
* Similar to retinal detachment fundoscopy is key in diagnosing
* Painless loss of vision
* Floaters
* Flashing lights (photopsia)
95
Management of posterior vitreous detachment?
None necessary – symptoms improve as brain adjusts
96
What is a vitreous haemorrhage?
Bleeding into vitreous humour.
97
Presentation of a vitreous haemorrhage?
* Mild – floaters
* Severe:
* Painless sudden loss of vision
* Retina difficult to view on fundoscopy
98
Describe the vision loss in vitreous haemorrhage
Painless sudden loss of vision
99
What is the most common cause of vitreous haemorrhage?
Diabetic retinopathy
100
Give some risk factors for vitreous haemorrhage
* Diabetic retinopathy – most common cause
* Retinal tear or detachment
* Posterior vitreous detachment
101
What is retinal artery occlusion?
Block of blood flow through the **central retinal vein** that supplies blood to the **retina**. It is a branch of the **ophthalmic** **artery** which is a branch of the internal carotid artery.
102
What is the retinal artery a branch of?
It is a branch of the ophthalmic artery which is a branch of the internal carotid artery.
103
Is retinal artery or central retinal vein occlusion more common?
Central retinal vein occlusion
104
What is the most common cause of retinal artery occlusion?
Atherosclerosis
105
Give 2 causes of retinal artery occlusion
* Atherosclerosis
* Giant cell arteritis
106
WHow can giant cell arteritis cause retinal artery occlusion?
Vasculitis affecting ophthalmic or central vein artery causes reduced blood flow
107
What are the risk factors for retinal artery occlusion?
Same as CVS disease
108
Describe the vision loss in retinal artery occlusion
**Sudden painless loss of vision**
109
Describe the vision loss in retinal artery vs central vein occlusion
Retinal artery occlusion typically occurs more rapidly than CRVO
110
Describe fundoscopy results in retinal artery occlusion
**pale** **retina** (as blood can’t get to it) with **_cherry_ _red_ spot** at macula
111
What occurs in retinal vein occlusion
Blood clot (thrombus) forms in the retinal veins and blocks the drainage of blood from the retina. The central retinal vein runs through the optic nerve and is responsible for draining blood from the retina.
112
Describe the vision loss in retinal vein occlusion
**Sudden painless loss of vision**
113
Describe fundoscopy results in retinal vein occlusion
* **'Stormy-sunset**’ appearance
* Flame and blot **haemorrhages** (blood can’t get out
114
Risk factors for retinal vein occlusion?
* Old age
* HTN
* Diabetes mellitus
* Polycythaemia
* Arteriosclerosis
115
What condition is optic neuritis typically associated with?
Multiple sclerosis
116
Describe the visual problems in optic neuritis
* **Vision loss** typically progresses over **hours to days** (not ‘sudden’ loss of vision)
* Central scotoma – enlarged blind spot
* Impaired colour vision
* Relative afferent pupillary defect
* **Painful**
* Pain on ocular movement
* ‘Red desaturation’
117
Is optic neuritis painful?
Yes
118
Does optic neuritis affect colour vision?
Yes
119
Amaurosis fugax vs central retinal artery occlusion?
Both cause vision loss due to lack of blood supply.
CRAO is a medical emergency that may result in irreversible loss of vision → permanent
**Amaurosis fugax or "transient CRAO" → transient.**
