Visual Failure Flashcards
1
Q
The commonest cause of visual dysfunction is a
________
A
simple refractive error.
2
Q
The WHO defines blindness as ‘best visual acuity less than ______
A
3/60’,
3
Q
in Australia eligibility for the blind pension is ‘bilateral corrected visual acuity less than _________ or significant visual field loss’ (e.g. a patient can have 6/6 vision but severely restricted fields caused by chronic open-angle glaucoma).
A
6/60
4
Q
The commonest causes of sudden visual loss are
____ and ________
A
transient occlusion of the retinal artery (amaurosis
fugax) and migraine
5
Q
‘Flashing lights’ are caused by traction on the
retina and may have a serious connotation: the
commonest cause is________
A
vitreoretinal traction, which is
a classic cause of retinal detachment.
6
Q
The presence of floaters or ‘blobs’ in the visual
fields indicates pigment in the vitreous: causes
include _______ and _____
A
vitreous haemorrhage and vitreous detachment
7
Q
______is the commonest
cause of the acute onset of floaters, especially with
advancing age
A
Posterior vitreous detachment
8
Q
Retinal detachment has a tendency to occur in
________
A
short-sighted (myopic) people
9
Q
Suspect a _________ where objects look
smaller or straight lines are bent or distorted.
A
macular abnormality
10
Q
Central visual loss presents as
impairment of visual acuity and implies defective
_____ or __________
A
retinal image formation (through refractive error or
opacity in the ocular media) or macular or optic nerve
dysfunction
11
Q
It is important to differentiate the central field
loss of macular degeneration from the _________
A
hemianopia of a CVA.
12
Q
2 drugs which are oculotoxic
A
ethambutol and quinine/chloroquine
13
Q
Questions specific Sx
Presence of floaters → normal ageing (especially
≥ 55 years) with posterior vitreous detachment
or may indicate _____ or ______
A
haemorrhages or choroiditis
14
Q
Questions specific Sx
Flashing lights → normal ageing with posterior
vitreous detachment or indicates _______
A
traction on the
retinal
15
Q
Questions specific Sx
Coloured haloes around lights → ____ and _____
A
glaucoma and cataract
16
Q
Questions specific Sx
Zigzag lines → _________
A
migraine
17
Q
Questions specific Sx
Vision worse at night or in dim light →
A
retinitis
pigmentosa, hysteria, syphilitic retinitis
18
Q
Questions specific Sx
Headache → _____
A
temporal arteritis, migraine, benign intracranial hypertension
19
Q
Questions specific Sx
_________ → macular disease, optic
neuritis
A
Central scotomata
20
Q
Pain on moving eye → _________
A
retrobulbar neuritis
21
Q
Distortion, micropsia (smaller), macropsia
(larger) → _________
A
macular degeneration
22
Q
Visual field loss:
— central loss—_________
— total loss—______
— peripheral loss
A
macular disorder
arterial occlusion
23
Q
It is worth noting that if a patient repeatedly
knocks into people and objects on a particular
side (including traffic accidents), a _________
A
bitemporal or homonymous hemianopia should be suspected
24
Q
Almost half the causes of blindness are genetically determined, in contrast to the ____ and _______causes that predominate in third world countries.
A
nutritional and infective
25
About ________ of children will fail to develop proper vision in at least one eye.
3%
26
The eyes of all babies should be examined at birth
| and at ________
6 weeks
27
______ is defined as a reduction in visual acuity due
| to abnormal visual experience in early childhood.
Amblyopia
28
What is the cause of amblyopia
caused by interference with visual
| development during the early months and years of life.
29
Common causes of amblyopia
* strabismus
* large refractive defect, especially hypermetropia
* congenital cataract
30
The two serious squints are the ______and
______ones, which require early referral.
Transient squint and latent squint (occurs under
stress e.g. fatigue) usually are not a problem
constant
alternating
31
Always refer children with strabismus (squint)
| when first seen to exclude ocular pathology such as
retinoblastoma, congenital cataract and glaucoma,
| which would require emergency surgery
32
The younger
the child, the easier it is to treat amblyopia; it may
be irreversible if first detected later than _____
school
| age
33
Problems with cataracts in children
development of vision may be permanently impaired
| amblyopia
34
Cataracts are diagnosed by looking at
the _______and this should be a routine part of the
examination of a young child
red reflex
35
Common conditions
causing cataracts are ____ and _____
but most causes are unknown.
genetic disorders and rubella
36
Refractive errors, with the error greater in one eye,
| can cause _______
amblyopia
37
_______, although rare, is the commonest
intraocular tumour in childhood. It must be excluded
in any child presenting with a white pupil
Retinoblastoma
38
What reflex do RB patients have?
Such children also have the so-called ‘cat’s eye reflex’.
39
_______ in its various forms is
the commonest cause of visual deterioration in the
elderly
Macular degeneration
40
Most patients with a vision of ______
or worse in both eyes usually benefit from cataract
extraction, but some can cope with this level of vision
and rely on a good, well-placed (above and behind)
reading light
6/18
41
Sudden loss of vision in the elderly is suggestive
of__ and _______so this
problem should be checked
temporal arteritis or vascular embolism,
42
Pathophysio of devt of floaters
When the vitreous gel shrinks as part of the normal
ageing process, it tugs on the retina (rods and cones),
causing flashing lights. When the gel separates from
the retina, floaters (which may appear as dots, spots
or cobwebs) are seen
43
FLoates can also be soon in whom?
myopic or who have had eye surgery such
| as removal of cataracts
44
In the normal eye (emmetropia) light rays from
infinity are brought to a focus on the retina by the
_______ (contributing about two-thirds of the eye’s
refractive power) and the ______(one-third).
cornea
lens
45
the cornea is very important in refraction and
abnormalities such as _____ may cause severe
refractive problems
keratoconus
46
The process of ________ is required for
focusing closer objects. This process, which relies on the
action of ciliary muscles and lens elasticity, is usually
affected by ageing,
accommodation
47
Highly myopic eyes may develop____ or _____
retinal detachment or macular degeneration.
48
Mx of Myopia
• Glasses with a concave lens
• Contact lenses
• Consider radial keratotomy or excimer laser
surgery
49
This condition is more susceptible to closed angle
| glaucoma.
Hypermetropia (long-sightedness)
50
Hypermetropia (long-sightedness) is asstd with what condition in early childhood?
In early childhood it may be associated
| with convergent strabismus (squint).
51
There is a need for near correction with loss of
| accommodative power of the eye in the 40s. What condition?
Presbyopia
52
This creates the need for a corrective lens that is more
curved in one meridian than another because the
cornea does not have even curvature
Astigmatism
53
Cx of astigmatism
If uncorrected,
| this may cause headaches of ocular origin
54
_______ is one cause of astigmatism.
Conical
| cornea
55
If visual acuity is not
normalised by looking through a card with a 1 mm
pinhole, then the defective vision is not solely due to
a _______
refractive error.
56
The term ‘cataract’ describes any_________
lens opacity
57
Cataract causes gradual visual loss with
| normal direct___________
pupillary light reflex
58
Causes of progressive B visual loss
From the globe: ________
Chronic glaucoma
| Senile cataracts
59
Causes of progressive B visual loss
From the Retina: ________
```
Macular degeneration
Retinal disease:
• diabetic retinopathy
• retinitis pigmentosa
• choroidoretinitis
```
60
Causes of progressive B visual loss
From the Optic nerve
Optic neuropathies
Optic nerve compression (e.g.
aneurysm, glioma)
Toxic damage to optic nerves
61
Causes of progressive B visual loss
From the Optic chiasma
Chiasmal compression: pituitary
| adenoma, craniopharyngioma, etc.
62
Causes of progressive B visual loss
From the Occipital cortex
Tumours
| Degenerative conditions
63
The _______ is a reflection of the fundus when the
eye is viewed from a distance of about 60 cm (2 feet)
with the ophthalmoscope using a zero lens.
‘red reflex’
64
Contraindications for extraction of cataract include ____ and _____
intraocular inflammation and severe diabetic retinopathy
65
The removal of the cataractous lens requires
optical correction to restore vision and this is usually
performed with an __________
intraocular lens implant
66
For cataract, Complications are uncommon yet many patients may require _______ to clear any opacities that may develop behind the lens implant
YAG laser capsulotomy
67
What drugs can be given to post op cataract
— steroids (to reduce inflammation)
— antibiotics (to avoid infection)
— dilators (to prevent adhesions
68
Sunglasses, particularly those that wrap around and
| filter UV light, may offer protection against ______
cataract
| formation
69
_______ is the commonest cause of
| irreversible blindness in middle age
Chronic simple glaucoma
70
Features of chronic glaucoma
* Familial tendency
* No early signs or symptoms
* Central vision usually normal
* Progressive restriction of visual field
71
Findings in glaucoma
Tonometry
• Upper limit of normal is_______ mmHg
Ophthalmoscopy
• Optic disc cupping ______ of total disc area
22
>30%
72
Meds for glaucoma used for life
— timolol or betaxolol drops bd
73
What other drugs can be given for pts with glaucoma
— latanoprost drops, once daily
— pilocarpine drops qid
— dipivefrine drops bd
— acetazolamide (oral diuretics)
74
Primary degeneration of the retina is a hereditary
condition characterised by a degeneration of rods
and cones associated with displacement of melanincontaining cells from the pigment epithelium into the more superficial parts of the retina
Retinitis pigmentosa
75
Features of RP
* Begins as ______ in childhood
* Visual fields become_____
* Blind by _______
night blindness
concentrically narrowed (periphery to centre)
adolescence (sometimes up to middle age
76
What may delay progression of RP
Irreversible course—may be delayed by vitamin A
77
Ophtha findings of RP
• Irregular patches of dark pigment, especially at
periphery
• Optic atrophy
78
Pain and redness may be minimal with this chronic
inflammation. If untreated, visual loss often develops
from secondary glaucoma and cataract.
Chronic uveitis
79
ocular problem with chronic uveitis>
The pupil is bound to the lens by synechiae and is distorted
80
```
AIDS may have serious ocular complications,
including
1
2
3
```
Kaposi sarcoma of the conjunctivae, retinal haemorrhage and vasculitis
81
Problem with HIVs
Another problem is ocular________, which presents as areas of opacification with haemorrhage
and exudates.
cytomegalovirus infection
82
_______ is transient loss of vision (partial or
complete) in one eye due to transient occlusion of a
retinal artery. It is painless and lasts less than 60 minutes
Amaurosis fugax
83
Amaurosis usually caused by an ______
embolus from an atheromatous carotid artery in the neck
84
In Aamurosis, The most common emboli are
______, which usually arise from an ulcerated
plaque
cholesterol emboli
85
Unilateral loss of vision provoked by activities such as
walking, bending or looking upwards is suggestive of
______
ocular ischaemia
86
What triggers ocular ischaemia?
It occurs in the presence of severe
extracranial vascular disease and may be triggered
by postural hypotension and stealing blood from the
retinal circulation.
87
What factors may cause RD
Retinal detachment may be caused by trauma, thin
retina (myopic people), previous surgery (e.g. cataract
operation), choroidal tumours, vitreous degeneration
or diabetic retinopathy
88
Classic eye sx of RD
‘A curtain came down over the eye’, grey cloud or
| black spot
89
In RD, small holes are usually tx by?
Small holes treated with laser or freezing probe
90
What may cause vitreous hemorrhage
spontaneous rupture of vessels, avulsion of vessels during retinal traction or bleeding from abnormal new vessels
91
Associations of vitreous hemorrhage
Associations include ocular trauma, diabetic retinopathy, tumour and retinal detachment.
92
SSx of Vitreous hemorrhage
* Sudden onset of floaters or ‘blobs’ in vision
| * May be sudden loss of vision
93
Ophthalmoscopy findings of Vitreous hemorrhage
Ophthalmoscopy may show reduced light reflex:
there may be clots of blood that move with the
vitreous (a black swirling cloud
94
Cause of CRAO
The cause is usually arterial obstruction by
| atherosclerosis, thrombi or emboli
95
SSx of CRAO
• Sudden loss of vision like a ‘curtain descending’
in one eye
• Vision not improved with 1 mm pinhole
• Usually no light perception
96
Ophthalmoscopy findings of CRAO
* Initially normal
* May see retinal emboli
* Classic ‘red cherry spot’ at macula
97
Mx of CRAO within 30 mins:
massage globe digitally through closed eyelids
(use rhythmic direct digital pressure)—may
______
• rebreathe carbon dioxide (paper bag) or inhale
_______
dislodge embolus
special CO 2 mixture (carbogen)
98
Prognosis of CRAO
Prognosis is poor. Significant recovery is unlikely
| unless treated immediately (within 30 minutes).
99
Factors which may lead to thrombosis
Thrombosis is associated with several possible
factors, such as hypertension, diabetes, anaemia,
glaucoma and hyperlipidaemia. It usually occurs in
elderly patients.
100
SSx of Central retinal vein thrombosis
• Sudden loss of central vision in one eye (if macula
involved): can be gradual over days
• Vision not improved with 1 mm pinhole
101
Opthalmoscopy findings of Central retinal vein thrombosis
Ophthalmoscopy shows swollen disc and multiple
| retinal haemorrhages, ‘stormy sunset’ appearance
102
T or F,
In Central retinal vein thrombosis
No immediate treatment is effective
No immediate treatment is effective
103
In Central retinal vein thrombosis
_________may be necessary in later stages if
neovascularisation develops to prevent thrombotic
glaucoma.
Laser photocoagulation
104
2 types of macular degeneration:
1
2
There are two types: exudative or ‘wet’ (acute), and
| pigmentary or ‘dry’ (slow onset).
105
________is caused by choroidal neovascular
membranes that develop under the retina of
the macular area and leak fluid or bleed. It is a
serious disorder
‘Wet’ MD
106
‘Dry’ MD (9 out of 10 cases of MD) develops
| ________ and usually ______
slowly and is always painless
107
Ssx of MD
* Sudden fading of central vision (see FIG 77.6 )
* Distortion of vision
* Straight lines may seem wavy and objects distorted
108
Visual fields of pts with MD
* Central vision eventually completely lost
| * Peripheral fields normal
109
What can be seen in the Amsler grid in pts with MD
Use a grid pattern (Amsler chart): shows
| distorted lines
110
Ophtalmoscopy findings of MD
* White exudates, haemorrhage in retina
| * Macula may look normal or raised
111
What is the Tx for wet MD
For ‘wet’ MD refer urgently for treatment, which
is currently based on injection of antivascular
endothelial growth factor drugs (ranibizumab
or bevacizumab) into the vitreous humour
112
What is the Tx for dry MD
No treatment is available to stop or reverse MD
113
Age-Related Eye Disease Study provided confirmatory
evidence that the chronic pigmentation
type responds to free-radical treatment with the
antioxidants vitamins A, C, E, and zinc using betacarotene,
15 mg; vitamin C, 500 mg; vitamin E,
400 IU; and 80 mg zinc oxide
114
With _____________there is
a risk of sudden and often bilateral occlusion of the
short ciliary arteries supplying the optic nerves, with
or without central retinal artery involvement.
temporal arteritis (giant cell arteritis)
115
What vision is lost in pts with temporal arteritis
Sudden loss of central vision in one eye (central
| scotoma)
116
Neuro PE of pts with temporal arteritis
Afferent pupil defect on affected side
117
Labs of pts with temporal arteritis
Usually elevated ESR >40 mm
118
Ophthalmoscopy findigs of temporal arteritis
Ophthalmoscopy shows optic disc swollen at first,
| then atrophic. The disc may appear quite normal
119
Tx for temporal arteritis
• Immediate corticosteroids (60–100 mg
| prednisolone daily for at least 1 week
120
In pts with temporal arteritis
What to do if there is a localised tender area)
Biopsy temporal artery
121
Migraine may present with symptoms of visual loss.
| Associated headache and nausea may not be present
Retinal migraine
122
SSx of retinal migraine
* Zigzag lines or lights
| * Multicoloured flashing lights
123
What condition
The vitreous body collapses and detaches from the
retina. It may lead to retinal detachment
Posterior vitreous detachment
124
Ssx of Posterior vitreous detachment
* Sudden onset of floaters
* Visual acuity usually normal
* Flashing lights indicate traction on the retina
125
Causes of Optic (retrobulbar) neuritis
Causes include multiple sclerosis, neurosyphilis and
| toxins
126
What vision is lost in Optic (retrobulbar) neuritis
* Usually a central field loss (central scotoma)
| * Afferent pupil defect on affected side
127
Ophtha findings of Optic (retrobulbar) neuritis
• Optic disc swollen if ‘inflammation’ anterior in
nerve
• Optic atrophy appears later
• Disc pallor is an invariable sequel
128
Patients with ________ typically suffer from
| ocular pain or discomfort and reduced vision
corneal conditions
129
```
Inflammation of the cornea—keratitis—is
caused by factors such as
1
2
3
4
```
ultraviolet light e.g. ‘arc eye’, herpes simplex, herpes zoster ophthalmicus and the dangerous ‘microbial keratitis
130
______ is an ophthalmological emergency that should be
considered in the contact lens wearer presenting
with pain and reduced vision.
Bacterial keratitis
131
Pittfalls
• Mistaking the coloured haloes of________for
migraine.
• Failing to appreciate the presence of retinal
detachment in the presence of______
glaucoma
minimal visual
impairment
132
Pittfalls
• Omitting to consider ______as a cause
of sudden visual failure in the elderly.
• Using eyedrops to dilate the pupil (for fundal
examination) in the presence of _______
temporal arteritis
glaucoma
133
Tonometry is advised routinely for all people over
______ years; those over 60 years should have tests
every 2 years
40
134
T or F
Any family history of glaucoma requires tonometry
at earliest age
T
135
Temporal arteritis is an important cause of _____
retinal artery occlusion
136
Suspect field defect due to ________ if
| people are misjudging when driving.
chiasmal compression
137
Central retinal artery occlusion may be overcome
| by ________
early rapid lowering of intraocular pressure
138
Keep in mind antioxidant therapy (vitamins and
| minerals) for________
chronic macular degeneration
139
Consider _________ foremost if there is a
past history of transient visual failure, especially
with eye pain
multiple sclerosis
140
Considerations for the ff time scales
Sudden: less than 1 hour
```
Amaurosis fugax
Central retinal artery occlusion
Hemianopias from ischaemia (emboli)
Migraine
Vitreous haemorrhage
Acute angle glaucoma
Papilloedema
```
141
Considerations for the ff time scales
Within 24 hours
1
2
Central retinal vein occlusion
| Hysteria
142
Considerations for the ff time scales
Less than 7 days
Retinal detachment
Optic neuritis
Acute macular problems
143
Considerations for the ff time scales
Up to several weeks (variable)
Choroiditis
| Malignant hypertension
144
Considerations for the ff time scales
Gradual
```
Compression of visual pathways
Chronic glaucoma
Cataracts
Diabetic maculopathy
Retinitis pigmentosa
Macular degeneration
Refractive errors
```
