Ophthalmology Flashcards
(172 cards)
1
Q
sclera
A
white of the eye
2
Q
conjunctiva
A
covers sclera
3
Q
cornea
A
covers the iris
4
Q
where is the lens
A
sits behind the iris
5
Q
role of the lens
A
helps to refract light and focus it on the retina
changes shape to alter the focus distance (accommodation)
6
Q
how is lens attached
A
attached to the ciliary body via suspensory ligaments
7
Q
what composes outer layer of eye
A
sclera
cornea
8
Q
what composes middle layer of eye (uvea)
A
iris
ciliary body
choroid
9
Q
what composes inner layer of eye (retina)
A
macula
fovea
optic disc
10
Q
roles of the ciliary body
A
control iris
shape the lens
secrete aqueous humour
11
Q
circulation of aqueous humour
A
produced by ciliary body
circulates in posterior chamber (of anterior segment) and nourishes the lens
travels through pupil into anterior chamber (of anterior segment) and nourishes cornea
Absorbed at iridocorneal angle through trabecular meshwork at the canal of schlemm
12
Q
anterior segment of the eye
A
in front of the lens
split into anterior chamber and posterior chamber
anterior chamber
- between cornea and iris
posterior chamber
- between the iris and suspensory ligaments
13
Q
posterior segment of the eye
A
behind the lens
- contains the vitreous body (vitreous humour)
14
Q
where is the blind spot
A
the optic disc
15
Q
mneumonic to rememeber eye muscle innervation
A
LR6 SO4 AO3
16
Q
topical Abx
A
chloramphenicol
ofloxacin
17
Q
s/e of topical steroids for eyes
A
local
- cataracts
- glaucoma
systemic
- weight gain
- diabetes
- thinning skin
- gastric ulceration
- osteoporosis
18
Q
List drug classes used in glaucoma Tx
A
prostaglandins beta blockers carbonic anhydrase inhibitors sympathomimetics parasympathomimetics
19
Q
mechanism of topical prostaglandins
A
increase uveoscleral outflow
20
Q
examples of prostaglandins
A
latanoprost
21
Q
s/e of prostaglandins
A
increase eyelash length
segmental iris colour change
dehydrates periorbital fat
22
Q
mechanism of beta blockers
A
decrease aqueous humour production
23
Q
examples of beta blockers
A
timolol
24
Q
s/e of beta blockers
A
systemic absorption
tiredness
25
mechanism of carbonic anhdrase inhibtors
decrease aqueous humour production
26
examples of carbonic anhydrase inhibitors
dorzolamide
| acetozolamide
27
s/e of carbonic anhydrase inhibitors
short term use only - kidney damage
| acetozolamide is oral and has systemic effects
28
examples of sympathomimetics
adrenaline
29
s/e of sympathomimetics
pupil dilation
30
mechanism of parasympathomimetics
increase uveoscleral outflow
31
examples of parasympathomimetics
pilocarpine
32
s/e of parasympathomimetics
pupil constriction
33
most common cause of endophthalmitis
post-cataract surgery
34
causative organism endophthalmitis
s. epidermidis
35
risk factors for AACG
hypermetropia (long-sightedness)
| pupil dilation
36
presentation AACG
```
red eye
n+v
pain ++
fixed mid dilated pupil
photophobia
reduced visual acuity
systemically unwell
```
37
characteristic visual field testing in AACG
arching
38
Mx AACG
```
IV Diamox (Acetozolamide)
Mannitol
Pilocarpine when IOP <50mmHg (constricts pupil)
```
39
causes of scleritis
connective tissue diseases - always investigate further
40
Mx scleritis
topical NSAIDs
41
violaceous hue
scleritis
42
cause of orbital cellulitis
extension from sinuses
43
preorbital cellulitis
little pain on eye movements
no reduced eye movements
no reduced visual acuity
44
Mx orbital cellulitis
IV Abx - ceftriaxone, fluclox + met
45
associations with episcleritis
gout
| tiredness
46
Mx episcleritis
self-limiting - can give lubricants
give NSAIDS if not resolving
47
presentation anterior uveitis
```
red eye
pain ++
photophobia
hypoyon
keratitic precipitates
posterior synechiae
```
48
Mx anterior uveitis
```
Topical steroids (hrly, reduce gradually) +
Mydriatics - tropicamide or cyclopentolate (dilates pupil and prevents posterior synechiae)
```
49
presentation bacterial keratitis
```
red eye
pain ++
reduced visual acuity
photophobia
purulent discharge
white corneal opacity seen with naked eye
```
50
Ix bacterial keratitis
corneal scrape form gram stain and culture
51
Mx bacterial keratitis
Topical Abx - ofloxacin
52
linear branching dendritic ulcer
herpes simplex corneal ulcer/keratitis
53
presentation adenoviral keratitis
bilateral
| follows URTI
54
organism usually causing fungal keratitis
aspergillus
55
who gets fungal keratitis
farmers or gardeners
| Hx of trauma from vegetation
56
organism causing protozoal keratitis
acanthomoeba
57
who gets protozoal keratitis
contact lens wearers
58
most common cause of viral conjunctivitis
adenovirus
59
Mx viral conjunctivitis
self-limitng +/- aciclovir if needed
60
Mx bacterial conjunctivitis
mild - mod: erythromycin
| mod -sev: ofloxacin
61
Mx gonorrhoeal conjunctivitis
ceftriaxone + doxycycline
62
Mx chlamydial conjunctivitis
topical azithromycin and doxycycline
63
Mx allergic conjunctivitis
mild: cold compresses
mod: mast cell stabiliser + antihistamines
severe: + corticosteroid
64
seborrhoeic anterior blepharitis
++ dandruff
teepee sign
lashes themselves are unaffected
65
squamous anterior blepharitis
lashes affected - distorted
66
posterior blepharitis
inflammation of the meibomian glands
| tarsal glands swollen and outpouching
67
risk factors for subconjunctival haemorrhage
blood thinners
elderly
truama
HTN
68
most common cause of vitreous haemorrhage
diabetic retinopathy
69
presentation vitreous haemorrhage
sudden painless unilateral loss of vision
red hue to vision
floaters/dark spots in vision
70
Mx vitreous haemorrhage
usually spontaneously resorbs
| if dense - vitrectomy
71
Ix if retina cant be seen on ophthalmoscope e.g. due to bleed
b-scan ultrasound
72
causes of retinal detachment
primary - traction (ageing process - vitreous gel becomes more liquid)
secondary - trauma, post-inflammatory, CTDs, myopia
73
presentation retinal detachment
```
the 4 F's
floaters
flashes
field loss
fall in acuity
```
dense shadow that starts peripherally and progresses towards central vision
central vision lost if macula affected
74
Mx retinal tear
laser
75
Mx retinal detachment
external approach - scleral buckle
internal approach - vitrectomy
76
presentation CRAO
sudden painless loss of vision (counting fingers)
pale oedematous retina with cherry red spot
RAPD
77
Ix CRAO
need to rule out GCA - do ESR, CRP
fluorescein angiography
carotid artery imaging
78
Mx CRAO
prognosis v poor - aim is to dislodge the clot
ocular massage
IV acetozolamide
paper bag breathing
anterior chamber paracentesis
79
curtain coming down
amaurosis fugax
80
what is amaurosis fugax
transient CRAO
81
Mx amaurosis fugax
immediate referral !
82
presentation CRVO
sudden painless loss of vision
dark retina
RAPD
swollen disc
+/- neovascularisation
+/- macular oedema
83
Mx CRVO
no ischaemia - observe 3m
ischaemia - observe 4-6w
ischaemia + neovascularisation - panretinal photocoagulation
84
Ix CRVO
fluorescein angiography
| optical coherance tomography (OCT)
85
risk factors for cataracts
down's syndrome
long term steroid use
hypocalcaemia
diabetes
86
sub types of cataract
nuclear sclerotic
posterior subcapsular
cortical
mature
87
Mx cataracts
phaecoemulsification with intraocular lens implantation
88
what is given post op cataracts
steroids and chloramphenicol 4xday for 4w
89
complications post-op cataracts
retinal detachment
endophthalmitis
posterior capsule rupture
posterior capsule opacification
90
what is the characteristic finding of ARMD
drusen - calcium deposits due to axonal degeneration
91
major risk factor for ARMD
smoking
92
dry type ARMD
geographic atrophy of the macula
93
wet type ARMD
neovascularisation of the macula - eye grows new vessels to repair the damage from dry type
94
presentation dry type ARMD
gradual central vision loss
| absent opic cup and abnormal branching patterns
95
Mx dry type ARMD
supportive - vision aids
stop smoking
blind registration
96
presentation wet type ARMD
sudden central vision loss
97
Mx wet type ARMD
anti-VGEF (ranibizumab) - prevents new vessel growth
98
what is open angle glaucoma
optic neuropathy and visual field loss due to clogging up of trabecular meshwork which blocks the drainage of aqueous humour
99
presentation open angle glaucoma
no symp till late - screened for by optometrists
increase cup to disc ratio (>0.4) - caused by loss of nerve fibres
peripheral vision loss
+/- raised IOP
100
Mx open angle glaucoma
```
prostaglandins
beta blockers
carbonic anhydrase inhibitors
sympathomimetics
parsympathomimetics
```
surgery - trabeculectomy
101
optic nerve lesion - visual field defect
unilateral field loss
102
causes of an optic nerve lesion
ischaemic optic neuropathy (arteritic or non-arteritic)
| optic neuritis
103
optic chiasm lesion - visual field defect
bitemporal hemianopia
104
optic tract lesion - visual field defect
homonymous hemianopia
105
parietal optic radiation lesion - visual field defect
contralateral inferior quadrantanopia
106
temporal optic radiation lesion - visual field defect
contralateral superior quadrantanopia
107
visual cortex lesion - visual field defect
homonymous hemianopia with macular sparing
108
presentation of RAPD
when light is shone in eye - it dilates because there is a problem with the optic nerve communicating to the brain
109
what is horners syndrome
lesion in the sympathetic pathway
110
causes of horners syndrome
pancoast tumour
carotid/aortic aneurysms
congenital
111
presentation of congenital horners syndrome
will have diff coloured eyes
112
presentation horners syndrome
pupil constriction
ptosis
reduced ipsilateral sweating
113
holmes adie pupil
dilated
114
argyll robertson pupil
constricted pupil - associated with neurosyphilis
115
internuclear ophthalmoplegia
affected eye has impaired adduction
116
cause of internuclear ophthalmoplegia
issue with medial longitudinal fascia
117
presentation of internuclear ophthalmoplegia
(say R eye is affected)
fine on looking to the right side - eye can abduct fine
when looking to the left - right eye wont be able to, and left eye will have nystagmus
118
presentation CN III palsy
dilated pupil
| down and out
119
painful third nerve palsy
aneurysm
120
presentation CN IV palsy
eye floats upwards
| excylotorsion (head tils)
121
cause of CN VI palsy
increased ICP (pressed against petrous bone)
122
presentation CN VI palsy
convergent squint of affected eye
123
tropia
= manifest squint
124
phoria
= latent squint
125
esotropia/esophoria
eye is IN
you see OUTWARD movement at cover test
126
exotropia/exophoria
eye is OUT
you see INWARD movement at cover test
127
hypertropia/hyperphoria
eye is HIGHER
128
hypotropia/hypophoria
eye is LOWER
129
duanes retraction syndrome
hypoplastic IVth nerve
| limited abduction and global retraction
130
browns syndrome
problem with SO, eye is elevated more than it should be
131
MX adult squint
non-surgical: temporary prisms, botox injection to temporarily paralse EOM
surgical: EOM surgery
132
amblyopia
lazy eye
| impairment of vision without any clinically detectable abnormality of the eye or visual pathway
133
classification of amblyopia
ametropic
strabismic
anisometropic
stimulus deprivation
134
cause of an ametropic amblyopia
bilateral uncorrected refractive error
135
cause of a strabismic amblyopia
the squinting eye is being suppressed
136
cause of an anisometropic amblyopia
an unequal refractive error
137
cause of a stimulus deprivation amblyopia
congenital cataract or ptosis
138
Mx of amblyopia
occlusion therapy:
partial - patch for max 6h/d
total - atropine 1% into good eye
139
what is the problem in myopic people
short sighted
| eye is too big so light focusses in front of the retina
140
type of lens needed for myopia
concave - takes power away from the eye so light focusses on the retina
141
what is the problem in hypermetropic people
long sighted
| eye is too small so light focusses behind the retina
142
type of lens needed for hypermetropia
convex - adds power to the eye so light focusses on the retina
143
astigmatism
light doesnt focus evenly on the retina
144
presbyopia
natural degeneration in the lens that occurs with age
145
type of lens needed for presbyopia
convex - add power to eye
146
signs of diabetic retinopathy/maculopathy
microaneurysms
dot/blot haemorrhages
cotton wool spots
hard exudates
147
cause of cotton wool spots
swelling of nerve axons that appear fluffy and white against the retina
148
cause of hard exudates
yellow deposits on the retina due to plasma leakage from capillaries
149
stages of non-proliferative diabetic retinopathy
mild, moderate, severe
150
mild non-proliferative diabetic retinopathy
only microaneurysms present
| at least one dot haemorrhage
151
moderate non-proliferative diabetic retinopathy
4 or more haemorrhages, but not in all 4 quadrants
152
severe non-proliferative diabetic retinopathy
implies a "busy fundus"
| large amounts of haemorrhage and microaneurysm formation in all 4 quadrants
153
what characterises proliferative diabetic retinopathy
new vessel formation (VGEF)
154
Mx diabetic retinopathy
no retinopathy - screen 12m
mild non-proliferative - screen 12m
mod non-proliferative - screen 6m
severe non-proliferative - refer to ophthal
proliferative - urgent refer to ophthal
155
Mx proliferative diabetic retinopathy
retinal laser photocoagulation
156
grading of diabetic maculopathy
based on the location of the changes with respect to the fovea
1. no maculopathy
2. observable maculopathy - exudates between 1 and 2 disc diameters from the fovea
3. referrable maculopathy - exudates < 1 disc diameter from the fovea
157
Mx observable maculopathy
resecreen 6m
158
Mx referable maculopathy
laser photocoagulation
159
stage I hypertensive retinopathy
silver or copper wiring
160
stage II hypertensive retinopathy
arteriovenous nipping
161
stage III hypertensive retinopathy
cotton wool exudates
| flame and blot haemorrhages
162
stage IV hypertensive retinopathy
papilloedema
163
test to see how far back into eye a penetrating trauma goes
siedels test - fluorescein will be diluted as it leaks back through to the front of the eye
164
Mx corneal abrasion
chloramphenicol - as preventative to bacteria
| usually take 24-48h to heal
165
sympathetic ophthalmia
a bilateral granulomatous uveitis due to trauma to one eye, thought to be autoimmune
166
Mx sympathetic ophthalmia
steroids and mydriatics
167
causes of alteration in colour of red reflex
aymmetrical camera shot
| retinoblastoma
168
cause of opactiy of red reflex
cataract
169
causes of no/black red reflex
retinoblastoma
| retinal detachment
170
Mx retinoblastoma
enucleation
171
Mx blocked nasolacrimal duct in kids
bathe and massage sac
| most spontaneously resolve
172
Mx preorbital cellulitis
IV co-amoxiclav
