content Flashcards
1
Q
definition of glaucoma
A
optic nerve damage due to a significant rise in intraocular pressure caused by a blockage in aqueous humour trying to escape the eye
2
Q
anatomy of the chambers of the eye
A
- anterior = between cornea and iris
- posterior = between iris and lens
- vitreous = between lens and optic nerve
3
Q
normal intraocular pressure
A
10-21mmHg
4
Q
anatomy of the aqueous humour in the eye
A
- produced by ciliary body
- flows around lens and under iris, through anterior chamber and through trabecular meshwork into the canal of schlemm
- then enters general circulation
5
Q
pathophysiology of open-angle glaucoma
A
gradual increase in resistance through trabecular meshwork making it more difficult for aqueous humour to flow through and exit the eye
-> slow and chronic onset of glaucoma
6
Q
pathophysiology of acute angle-closure glaucoma
A
iris bulges forward and seals off trabecular meshwork from the anterior chamber, preventing aqueous humour being able to drain away
-> continual build-up of pressure = emergency
7
Q
ophthalmoscopy finding in glaucoma
A
cupping of the optic disc (centre of the normal optic disc usually <1/2 size of disc but pressure on eye in glaucoma causes it to increase to >1/2 size)
8
Q
risk factors for open-angle glaucoma
A
- increasing age
- FHx
- Black ethnic origin
- nearsightedness (myopia)
9
Q
presentation of open-angle glaucoma
A
- may be picked up on routine screening
- gradual loss of peripheral vision -> tunnel vision
- gradual onset of fluctuating pain, headaches, blurred vision and halos around lights
10
Q
how to measure intraocular pressure
A
- non-contact tonometry -> puff of air at cornea and measuring corneal response
- golwmann applanation tonometry -> contact with cornea and apply different pressures
11
Q
diagnosis of glaucoma ix
A
- goldmann applanation tonometry
- fundoscopy
- visual field assessment
12
Q
medical management of open-angle glaucoma
A
aim to reduce pressure
- prostaglandin analogue eye drops (latanoprost) increase uveoscleral outflow
- beta-blockers to reduce production of aqueous humour
- carbonic anhydrase inhibitors reduce production
- sympathomimetics reduce production and increase outflow
13
Q
when to treat open-angle glaucoma
A
pressure of 24mmHg or above
14
Q
surgical management of open-angle glaucoma
A
trabeculectomy -> creating new channel from anterior chamber, through sclera to location under conjunctiva
produces ‘bleb’ where aqueous humour drains
15
Q
risk factors for closed-angle glaucoma
A
- increasing age
- female: male = 4:1
- FHx
- Chinese and East Asian (rare in Black ethnic origin)
- shallow anterior chamber
16
Q
medications which can precipitate angle-closure glaucoma
A
- adrenergic meds e.g. noradrenaline
- anticholinergic meds e.g. oxybutynin
- tricyclic antidepressants e.g. amitriptyline
17
Q
presentation of angle-closure glaucoma
A
- generally unwell
- severely painful red eye
- blurred vision
- halos around lights
- associated headache, nausea and vomiting
18
Q
examination findings in angle-closure glaucoma
A
- red eye
- teary
- hazy cornea
- decreased visual acuity
- dilation of affected pupil
- fixed pupil size
- firm eyeball on palpation
19
Q
initial mx of angle-closure glaucoma in primary care
A
- lie patient on their back without a pillow
- pilocarpine eye drops: 2% for blue eyes, 4% for brown eyes (mitotic agent)
- acetazolamide 500mg PO
- analgesia and antiemetic if required
20
Q
secondary care medical mx of angle-closure glaucoma
A
- pilocarpine
- acetazolamide
- hyperosmotic agents e.g. glycerol, mannitol
- timolol
- dorzolamide
- sympathomimetics
21
Q
definitive tx of angle-closure glaucoma
A
laser iridectomy -> laser to make hole in iris to allow aqueous humour to flow from posterior chamber into anterior chamber
22
Q
definition of age-related macular degeneration
A
degeneration in macular causing progressive deterioration in vision
23
Q
types of macular degeneration
A
wet (10%) -> worse prognosis
dry (90%)
24
Q
key finding on fundoscopy in macular degeneration
A
drusen = yellow deposits of proteins and lipids appear between retinal pigment epithelium and Bruch’s membrane
25
features of both types of macular degeneration
- drusen on fundoscopy
- atrophy of retinal pigment epithelium
- degeneration of photoreceptors
26
pathophysiology of wet macular degeneration
- development of new vessels growing from choroid layer into retina
- vessels leak fluid or blood and cause oedema and more rapid loss of vision
- chemical stimulating vessel development = vascular endothelial growth factor (VEGF)
27
risk factors for macular degeneration
- age
- smoking
- white or Chinese ethnic origin
- FHx
- CVD
28
presentation of macular degeneration
- gradual worsening central visual field loss
- reduced visual acuity
- crooked/wavy appearance to straight lines
29
examinations in suspected macular degeneration
- snellen chart (reduced acuity)
- scotoma (central patchy of vision loss)
- amsler grid test (distortion of straight lines)
- fundoscopy (drusen)
30
ix in suspected macular degeneration
- slit-lamp biomicroscopic fundus exam
- optical coherence tomography
- fluorescein angiography (see blood supply to retina)
31
mx of dry macular degeneration
lifestyle measures to slow progression:
- avoid smoking
- control BP
- vitamin supplementation
32
mx of wet macular degeneration
- anti-VEGF (vascular endothelial growth factor) e.g. ranibizumab, bevacizumab, pegaptanib
- injected directly into vitreous chamber once a month
- slow and even reverse progression by blocked neovascularization
33
definition of diabetic retinopathy
blood vessels in the retina are damaged by prolonged exposure to hyperglycaemia
34
pathophysiology of diabetic retinopathy
hyperglycaemia causes damage to retina small vessels and endothelial cells
increased vascular permeability leaks to leakage, blot haemorrhages and formation of hard exudates
35
what are cotton wool spots
fluffy white patches on the retina due to damaged nerve fibres e.g. diabetic or hypertensive retinopathy
36
fundoscopy findings in proliferative diabetic retinopathy
- cotton wool spots
- microaneurysms
- hard exudates
- blot haemorrhages
- neovascularization
37
classification of diabetic retinopathy
non-proliferative:
- mild: microaneurysms
- moderate: microaneurysms, blot haemorrhages, hard exudates, cotton wool spots and venous beading
- severe: blot haemorrhages and microaneurysms in 4 quadrants, venous beading in 2 quadrants, intraretinal microvascular abnormality
proliferative:
- neovascularization
- vitreous haemorrhage
38
complications of diabetic retinopathy
- retinal detachment
- vitreous haemorrhage
- rebeosis iridis (blood vessel formation in iris)
- optic neuropathy
- cataracts
39
mx of diabetic retinopathy
- laser photocoagulation
- anti-VEGF
- vitreoretinal surgery
40
definition of hypertensive retinopathy
damage to small blood vessels in the retina relating to systemic hypertension (either chronic or malignant hypertension)
41
fundoscopy findings in hypertensive retinopathy
- cotton wool spots
- silver wiring
- hard exudates
- arteriovenous nipping
- retinal haemorrhages
- papilloedema
42
classification of hypertensive retinopathy
Keith-Wagener classification
- stage 1 = mild narrowing of arterioles
- stage 2 = focal constriction of blood vessels and AV nipping
- stage 3 = cotton wool patches, exudates and haemorrhages
- stage 4 = papilloedema
43
mx of hypertensive retinopathy
control BP and other risk factors such as smoking and lipid levels
44
definition of cataracts
lens in the eye becomes cloudy and opaque leading to reduced visual acuity
45
risk factors for cataracts
- increasing age
- smoking
- alcohol
- diabetes
- steroids
- hypocalcaemia
46
presentation of cataracts
symptoms usually asymmetrical
- very slow reduction in vision
- progressive blurring
- change of colour vision (become more brown)
- starbursts appear around lights
47
mx of cataracts
- no intervention if manageable symptoms
| - cataract surgery -> drilling and breaking lens into pieces and replacing with artificial lens
48
complication of cataract surgery
endophthalmitis -> inflammation of inner contents of the eye, usually caused by infection
can lead to loss of vision and loss of the eye itself
49
mechanism of pupil constriction
circular muscles in the iris cause constriction via stimulation by parasympathetic nerves (CN III) using ACh
50
mechanism of pupil dilation
dilator muscles stimulated by sympathetic nervous system using adrenaline
51
causes of mydriasis (dilated pupil)
- CN III palsy
- raised ICP
- congenital
- trauma
- stimulants such as cocaine
- anticholinergics
52
causes of miosis (constricted pupil)
- Horners syndrome
- cluster headaches
- opiates
- nicotine
- pilocarpine
53
presentation of third nerve palsy
- ptosis (drooping of upper eyelid)
- dilated, non-reactive pupil
- divergent strabismus (squint) causing down and out position of eye
54
causes of third nerve palsy
- idiopathic
- tumour
- trauma
- cavernous sinus thrombosis
- posterior communicating artery aneurysm
- raised ICP
55
what is a partial third nerve palsy
sparing of the pupil -> indicates microvascular cause as the parasympathetic fibres are spared
may be due to: diabetes, hypertension, ischaemia
56
triad of horners syndrome
- ptosis
- miosis
- anhidrosis
may be enopthalmos (sunken eye)
57
anatomy of sympathetic nerves to the face
- arise from spinal cord in the chest (pre-ganglionic)
- enter sympathetic ganglion at base of neck and exit as post-ganglionic
- post-ganglionic travel to the head alongside internal carotid artery
58
how to differentiate between pre-ganglionic, central and post-ganglionic causes of horners syndrome
central lesions cause anhidrosis of arm and trunk as well as face
pre-ganglionic lesions cause anhidrosis of only the face
post-ganglionic lesions cause no anhidrosis
59
causes of horners syndrome and mnemonic
4 Ss (Sentral), 4 Ts (Torso - pre-ganglionic), 4 Cs (Cervical - post-ganglionic)
- S = stroke, mS, swelling (tumour), syringomyelia
- T = tumour (pancoast), trauma, thyroidectomy, top rib (cervical rib)
- C = carotid aneurysm, carotid artery dissection, cavernous sinus thrombosis, cluster headache
60
definition of blepharitis
inflammation of the eyelid margins
| causes gritty, itchy, drug eyes
61
mx of blepharitis
- hot compresses and gentle cleaning of eyelid margins
| - lubricating eye drops
62
pathophysiology of a stye
'hordeolum externum' = infection of glands of Zeis or glands of Moll (sweat/sebaceous glands) causing tender red lump along eyelid that may contain pus
'hordeolum internum' = infection of meibomian glands - deeper, more painful
63
tx of styes
hot compresses and analgesia
| consider topical abx if associated with conjunctivitis or persistent
64
definition of a chalazion
blockage and swelling of a meibomian gland 'meibomian cyst'
65
presentation of chalazion
swelling in eyelid not typically tender
| can be tender and red
66
tx of chalazion
hot compress and analgesia
| consider topical abx if acutely inflamed
67
definition of entropion
eyelid turns inwards with lashes against eyeball - can result in corneal damage and ulceration
68
mx of entropion
taping down eyelid
| surgical intervention as definitive tx
69
definition of ectropion
eyelid turns outwards with inner aspect of eyelid exposed (usually bottom lid)
can result in exposure keratopathy
70
mx of ectropion
mild cases don't require tx
lubricating eye drops
may require surgery
71
definition of periorbital cellulitis
eyelid and skin infection in front of the orbital septum
72
presentation of periorbital cellulitis
swelling, redness and hot skin around the eyelids and eye
73
ix in periorbital cellulitis
important to exclude orbital cellulitis (sight and life threatening) -> CT
74
mx of periorbital cellulitis
```
systemic abx (oral or IV)
may require admission as can develop into orbital cellulitis
```
75
definition of orbital cellulitis
infection around eyeball involving tissues behind orbital septum
76
features of orbital cellulitis which differentiate from periorbital
```
pain on eye movement
reduced eye movements
changes in vision
abnormal pupil reactions
forward movement of eyeball (proptosis)
```
77
mx of orbital cellulitis
medical emergency
admission + IV abx
may require surgical drainage
78
definition of conjunctivitis
inflammation of the conjunctiva (thin layer of tissue covering the inside of the eyelids and the sclera)
79
3 types of conjunctivitis
bacterial
viral
allergic
80
presentation of conjunctivitis
red eyes
bloodshot
itchy or gritty sensation
eye discharge
81
differentiating between bacterial and viral conjunctivitis
```
bacterial = purulent discharge and inflamed conjunctiva, worse in the morning, highly contagious
viral = clear discharge, associated with other symptoms (dry cough, sore throat), may have tender preauricular lymph nodes
```
82
causes of a painless red eye
- conjunctivitis
- episcleritis
- subconjunctival haemorrhage
83
causes of a painful red eye
- glaucoma
- anterior uveitis
- scleritis
- corneal abrasions or ulceration
- keratitis
- foreign body
- traumatic or chemical injury
84
mx of conjunctivitis
- usually self-resolving in 1-2 weeks
- advice on good hygiene to avoid spread
- clean eyes with cooled boiled water and cotton wool
- consider abx eye drops if bacterial
85
when to refer conjunctivitis for ophthalmology review
patients <1 month old
| neonatal conjunctivitis can be associated with gonococcal infection which can cause loss of sight
86
presentation of allergic conjunctivitis
swelling of conjunctival sac and eye lid with watery discharge and itch
87
mx of allergic conjunctivitis
antihistamines (oral or topical)
| topical mast-cell stabilisers
88
definition of anterior uveitis
inflammation in the anterior part of the uvea (iris, ciliary body and choroid)
89
pathophysiology of anterior uveitis
inflammation and immune cells in the anterior chamber - chamber is infiltrated by neutrophils, lymphocytes and macrophages
90
causes of anterior uveitis
- autoimmune
- infection
- trauma
- ischaemia
- malignancy
91
conditions associated with acute anterior uveitis
HLA B27:
- ankylosing spondylitis
- IBD
- reactive arthritis
92
conditions associated with chronic anterior uveitis
- sarcoidosis
- syphilis
- lyme disease
- TB
- herpes virus
93
presentation of anterior uveitis
- dull, aching, painful red eye
- ciliary flush (red ring)
- reduced visual acuity
- floaters and flashes
- miosis (constricted pupil)
- photophobia
- pain on movement
- excess lacrimation
- abnormally shaped pupil
- hypopyon (collection of WBC in anterior chamber seen as yellow fluid collection in iris with fluid level)
94
mx of anterior uveitis
- steroids
- cycloplegic-mydriatic meds (atropine eye drops) to dilate pupil and reduce pain
- immunosuppressants
- laser therapy, cryotherapy or surgery
95
definition of episcleritis
benign and self-limiting inflammation of episclera (outermost layer of sclera)
96
conditions associated with episcleritis
rheumatoid arthritis
| IBD
97
presentation of episcleritis
acute onset unilateral:
- no-mild pain
- segmental redness (patch in lateral sclera is common)
- foreign body sensation
- dilated episcleral vessels
- watering of eye, no discharge
98
mx of episcleritis
- self-limiting and resolves in 1-4 weeks
- lubricating eye drops for symptom relief
- simple analgesia, cold compress and safety net advice
- severe: systemic NSAIDs or topical steroid eye drops
99
definition of scleritis
inflammation of the whole thickness of the sclera
100
complication of scleritis
necrotising scleritis -> visual impairment but no pain, can lead to perforation of the sclera
101
conditions associated with scleritis
- rheumatoid arthritis
- SLE
- IBD
- sarcoidosis
- granulomatosis with polyangiitis
102
presentation of scleritis
- unilateral or bilateral
- severe pain, pain on movement
- photophobia
- eye watering
- reduced visual acuity
- abnormal pupil light reaction
- tenderness to palpation of eye
103
mx of scleritis
- consider underlying systemic condition
- NSAIDs (topical or systemic)
- steroids (topical or systemic)
- immunosuppression appropriate to underlying condition
104
mx of red eye with potentially sight-threatening cause
refer for same day assessment by ophthalmologist
105
causes of corneal abrasion
- contact lenses
- foreign bodies
- finger nails
- eyelashes
- entropion
106
what to consider in corneal abrasions associated with contact lenses
pseudomonas infection
107
presentation of corneal abrasion
- hx of contact lenses or foreign body
- painful red eye
- foreign body sensation
- watering eye
- blurring vision
- photophobia
108
diagnosis of corneal abrasion
fluorescein stain -> yellow/orange colour stain which collects in abrasions or ulcers
109
mx of corneal abrasion
- simple analgesia
- lubricating eye drops
- abx eye drops
- return in 1 week to check if healed
- cyclopentolate eye drops dilate pupil and improve symptoms
110
definition of keratitis
inflammation of the cornea
111
causes of keratitis
- viral: herpes simplex
- bacterial: pseudomonas, staphylococcus
- fungal: candida, aspergillus
- contact lens acute red eye (CLARE)
- exposure keratitis in ectropion
112
presentation of herpes keratitis
- painful red eye
- photophobia
- vesicles around eye
- foreign body sensation
- watering eye
- reduced visual acuity
113
diagnosing herpes keratitis
- fluorescein stain shows dendritic (branching) corneal ulcer
- slit-lamp examination
- corneal swabs/scrapings for culture/PCR
114
mx of herpes keratitis
- aciclovir (topical or oral)
- ganciclovir eye gel
- topical steroids if stromal keratitis
- may require corneal transplant due to scarring
115
definition of subconjunctival haemorrhage
one of small blood vessels in conjunctiva ruptures and releases blood into space between sclera and conjunctiva
116
conditions which predispose to subconjunctival haemorrhage
- hypertension
- bleeding disorders e.g. thrombocytopaenia
- whooping cough
- meds (warfarin, DOACs, antiplatelets)
- non-accidental injury
117
presentation of subconjunctival haemorrhage
- patch of bright red blood underneath conjunctiva and in front of sclera covering white of eye
- painless
- no vision changes
- hx of precipitating event e.g. coughing fit, heavy lifting
118
mx of subconjunctival haemorrhage
- resolve spontaneously without any tx in 2 weeks
- manage underlying/predisposing conditions such as HTN
- lubricating eye drops can help with symptoms
119
presentation of posterior vitreous detachment
- asymptomatic
- painless
- spots of vision loss
- floaters
- flashing lights
120
mx of posterior vitreous detachment
no tx necessary
| can predispose to retinal tears and retinal detachment
121
definition of retinal detachment
retina separates from choroid underneath, usually due to retinal tear that allows vitreous fluid to get under retina and fill space
122
risk factors for retinal detachment
- posterior vitreous detachment
- diabetic retinopathy
- trauma to eye
- retinal malignancy
- older age
- FHx
123
presentation of retinal detachment
- painless peripheral vision loss, often sudden like a shadow coming across
- blurred or distorted vision
- flashes, floaters
124
mx of retinal detachment
reattach retina and reduce traction/pressure + tx of retinal tears:
- vitrectomy (removal of vitreous body and replace with oil/gas)
- scleral buckling
- pneumatic retinopexy
125
mx of retinal tears
create adhesions between retina and choroid to prevent detachment:
- laser therapy
- cryotherapy
126
definition of central retinal vein occlusion
blood clot (thrombus) forms in retinal veins and blocks drainage of blood from retina
127
pathophysiology of central retinal vein occlusion
- clot in retinal veins causes blockage
- results in fluid/blood leakage causing macular oedema and retinal haemorrhage
- damage to retinal tissue and loss of vision
- stimulates release of VEGF => neovascularization
128
presentation of retinal vein occlusion
sudden painless loss of vision
129
risk factors for retinal vein occlusion
- hypertension
- high cholesterol
- diabetes
- smoking
- glaucoma
- SLE etc.
130
characteristic fundoscopy findings in retinal vein occlusion
- flame and blot haemorrhages
- optic disc oedema
- macula oedema
131
ix in retinal vein occlusion
check for associated conditions:
- FBC (leukaemia)
- ESR (inflammatory disorders)
- BP (HTN)
- glucose (DM)
132
mx of retinal vein occlusion
refer to ophthalmologist to tx macular oedema and prevent neovascularization:
- laser photocoagulation
- intravitreal steroids (dex implant)
- anti-VEGF
133
definition of central retinal artery occlusion
blockage to flow through retinal artery, normally secondary to atherosclerosis
134
aetiology of central retinal artery occlusion
- atherosclerosis
| - GCA
135
risk factors for central retinal artery occlusion
- older age
- FHx
- smoking & alcohol
- HTN
- DM
- poor diet
- inactivity
- obesity
- GCA: white females >50yo with GCA/PMR
136
presentation of central retinal artery occlusion
sudden painless loss of vision
137
signs of central retinal artery occlusion on examination
relative afferent pupillary defect (pupil in affected eye constricts more when light shone into other eye)
138
signs of central retinal artery occlusion on fundoscopy
- pale retina (ischaemia)
| - cherry-red spot (macula is thinner and shows red choroid below)
139
mx of retinal artery occlusion
- ESR and temporal artery biopsy to ix for GCA (-> high-dose steroids)
- attempt to dislodge thrombus
140
4 steps of retinal artery occlusion mx to attempt to dislodge thrombus
1. ocular massage
2. removal of fluid from ant chamber
3. inhale carbogen (CO2 + O2) to dilate artery
4. sublingual isosorbide dinitrate
141
long term tx of retinal artery occlusion
tx reversible risk factors
| secondary prevention of CVD
142
definition of retinitis pigmentosa
congenital inherited condition where there is degeneration of the rods and cones in the retina
143
presentation of retinitis pigmentosa
most cases start in childhood (FHx)
- night blindness (rods degenerate more than cones)
- peripheral vision lost before central vision
144
fundoscopy findings in retinitis pigmentosa
- pigmentation -> 'bone-spicule' pigmentation (looks like bone matrix)
- pigmentation most concentrated around mid-peripheral area
- associated narrowing of arterioles and waxy/pale appearance of optic disc
145
general mx of retinitis pigmentosa
- referral
- genetic counselling
- vision aids
- sunglasses to protect retina from accelerated damage
- driving limitations (inform DVLA)
- regular follow up
146
medical mx options for retinitis pigmentosa
- vitamin and antioxidant supplementation
- oral acetazolamide
- topical dorzolamide
- steroid injections
- anti-VEGF
147
differentials for painless vision loss
- retinal artery occlusion
- retinal vein occlusion
- retinal detachment
- episcleritis
- optic neuritis
- vitreous haemorrhage
148
differentials for painful vision loss
- acute angle-closure glaucoma
- scleritis
- anterior uveitis
