Ophthalmology Flashcards
Open Angle Glaucoma
what is a glaucoma
refers to the optic nerve damage that is caused by a significant rise in intraocular pressure
Open Angle Glaucoma
what is the raised intraocular pressure caused by in glaucomas
blockage in aqueous humour trying to escape the eye
Open Angle Glaucoma
the vitreous chamber of the eye is filled with ___
vitreous humour
where is the anterior chamber
between the cornea and the iris
where is the posterior chamber
between the lens and iris
the anterior and posterior chamber is filled with ___
aqueous humour which supplies nutrients to the cornea
what produces the aqueous humour
the ciliary body
describe the flow of aqueous humour
from the ciliary body
around the lens and under the iris
through the anterior chamber
through the trabecular meshwork
and into the canal of Schlemm
eventually entering the general circulation
what is the normal intraocular pressure
10-21 mmHg
how is intraocular pressure created
by the resistance to flow through the trabecular meshwork into the canal of Schlemm
Open Angle Glaucoma
pathophysiology
gradual increase in resistance through the trabecular meshwork
more difficult for aqueous humour to flow through the meshwork and exit the eye
pressure slowly builds within the eye and this gives a slow and chronic onset of glaucoma
Acute Angle-Closure Glaucoma
pathophysiology
the iris bulges forward and seals off the trabecular meshwork from the anterior chamber
preventing aqueous humour from being able to drain away
leading to a continual build-up of pressure
ophthalmology emergency
what causes cupping of the optic disc
increased pressure in the eye
what is in the centre of a normal optic disc
the optic cup, a small indent in the optic disc less than half the size of the optic disc
what is cupping
when there is raised intraocular pressure, the optic cup becomes larger as the pressure in the eye puts pressure on that indent making it wider and deeper
what is an abnormal optic cup size
greater than 0.5 the size of the optic disc
Open Angle Glaucoma
RFs (4)
- increasing age
- FH
- black ethnic origin
- myopia (short sighted)
Open Angle Glaucoma
presentation
- asymptomatic for a long period of time
- affects peripheral vision first
- gradually peripheral vision closes until they experience tunnel vision
- gradual onset of fluctuating pain
- headaches
- blurred vision
- halos appearing around lights esp at night
Open Angle Glaucoma
dx
routine screening when attending optometry for eye check
Non-contact tonometry
Open Angle Glaucoma
what is non-contact tonometry
the commonly used machine for estimating intraocular pressure by opticians
shoots a puff of air at the cornea and measures the corneal response to that air
Open Angle Glaucoma
what is Goldmann applanation tonometry
the gold standard way to measure introcular pressure
special device mounted on slit lamp that makes contact with the cornea and applies different pressures to the front of the cornea to get an accurate measurement of what the intraocular pressure is
Open Angle Glaucoma
dx and inx
Goldmann applanation tonometry: intraocular pressure
Fundoscopy: optic disc cupping and optic nerve health
Visual field assessment: peripheral vision loss
Open Angle Glaucoma
aim of mnx
reduce intraocular pressure
Open Angle Glaucoma
when is treatment started
when intraocular pressure is 24 mmHg or above
Open Angle Glaucoma
first line mnx
Prostaglandin analogue eye drops eg. latanoprost
Open Angle Glaucoma
how does latanoprost work
prostaglandin analogue eye drops increase uveoscleral outflow
Open Angle Glaucoma
prostaglandin analogue eye drop SEs eg. latanoprost
- eyelash growth
- eyelid pigmentation
- iris pigmentation (browning)
Open Angle Glaucoma
other mnx options apart from latanoprost
- BB e.g. timolol
- carbonic anhydrase inhibitors e.g. dorzolamide
- sympathomimetics e.g. brimonidine
Trabeculectomy
Open Angle Glaucoma
how do BB work
reduce the production of aqueous humour
Open Angle Glaucoma
how do carbonic anhydrase inhibitors work
reduce the production of aqueous humour
Open Angle Glaucoma
how do sympathomimetics work
reduce the production of aqueous fluid and increase uveoscleral outflow
Open Angle Glaucoma
when is a trabeculectomy indicated
where eye drops are ineffective
Open Angle Glaucoma
what is involved in a trabeculectomy
creating a new channel from the anterior chamber, through the sclera to a location under the conjunctiva
it causes a ‘bleb’ under the conjunctiva where the aqueous humour drains
it is then reabsorbed from this bleb into the general circulation
Acute Angle Close Glaucoma
cause
when the iris bulges forward and seals off the trabecular meshwork from the anterior chamber, preventing aqueous humour from being able to drain away
continual build up of pressure in the eye, esp in the posterior chamber which causes pressure behind the iris and worsens the closure of the angle
Acute Angle Close Glaucoma
RFs (5)
- increasing age
- 4F:1M
- FH
- Chinese + East Asian ethnic origin
- shallow anterior chamber
Acute Angle Close Glaucoma
what medications can precipitate acute angle-closure glaucoma
- Adrenergics: noradrenalin
- Anticholinergics: oxybutynin + solifenacin
- TCA: amitriptyline, which have anticholinergic effects
Acute Angle Close Glaucoma
presentation
- generally unwell in themselves
- severely painful red eye
- blurred vision
- halos around lights
- headache, N+V
Acute Angle Close Glaucoma
examination findings (7)
- red eye
- teary
- hazy cornea
- decreased visual acuity
- dilatation of the affected pupil
- fixed pupil size
- firm eyeball on palpation
Acute Angle Close Glaucoma
initial mnx
same day assessment by opthalmologist
while waiting for an ambulance:
- lie pt on their back without a pillow
- pilocarpine eye drops
- PO acetazolamide 500mg
- analgesia + antiemetic PRN
Acute Angle Close Glaucoma
initial mnx: if blue eyes what % pilocarpine do you give
2%
Acute Angle Close Glaucoma
initial mnx: if brown eyes what % pilocarpine do you give
4%
Acute Angle Close Glaucoma
how does pilocarpine act?
Miotic agent: acts on the muscarinic receptors in the sphincter muscles in the iris and causes constriction of the pupil
also causes ciliary muscle contraction
these 2 effects cause the pathway for the flow of aq humour from the ciliary body, around the iris and into the trabecular meshwork to open up
Acute Angle Close Glaucoma
how does Acetazolamide work
carbonic anhydrase inhibitor.
This reduces the production of aq humour
Acute Angle Close Glaucoma
secondary care mnx to reduce the pressure
- Pilocarpine
- Acetazolamide (oral or IV)
- Hyperosmotic agents: glycerol, mannitol
- Timolol
- Dorzolamide
- Brimonidine
Acute Angle Close Glaucoma
how do hyperosmotic agents like glycerol or mannitol work
they increase the osmotic gR between the blood and fluid in the eye
Acute Angle Close Glaucoma
how does Timolol work
BB: reduces production of the aq humour
Acute Angle Close Glaucoma
how does Dorzolamide work
carbonic anhydrase inhibitor: reduces the production of aq humour
Acute Angle Close Glaucoma
how does Brimonidine work
sympathomimetic: reduces the production of aq fluid and increases uveoscleral outflow
Acute Angle Close Glaucoma
definitive trx
laser iridotomy
Acute Angle Close Glaucoma
what does laser iridotomy involve
using a laser to make a hole in the iris to allow the aq humour to flow from the posterior chamber into the anterior chamber
this relieves pressure that was pushing the iris against the cornea and allow the humour to drain
Age Related Macular Degeneration
what is it
a condition where there is degeneration in the macula that cause a progressive deterioration in vision
in the UK, what is the most common cause of blindness
Age Related Macular Degeneration
Age Related Macular Degeneration
key finding
drusen seen during fundoscopy
Age Related Macular Degeneration
what are the 2 types
wet (10%) - worse prognosis
and dry
Age Related Macular Degeneration
what are the 4 key layers of the macula
bottom: choroid layer
Bruch’s membrane
Retinal pigment epithelium
Top: photoreceptors
Age Related Macular Degeneration
what does the choroid layer of the macular contain
blood vessels that provide blood supply to the macula
Age Related Macular Degeneration
what are drunsen
yellow deposits of proteins and lipids that appear between the retinal pigment epithelium and Bruch’s membrane
Larger and greater numbers of drusen can be an early sign of ____
macular degeneration
Age Related Macular Degeneration
common features of both wet and dry AMD (2)
- atrophy of the retinal pigment epithelium
- degeneration of the photoreceptors
Age Related Macular Degeneration
pathophysiology of wet AMD
development of new vessels growing from the choroid layer into the retina
These vessels can leak fluid or blood and cause oedema and more rapid loss of vision
Age Related Macular Degeneration
name a key chemical that stimulates the development of new vessels
vascular endothelial growth factor (VEGF)
Age Related Macular Degeneration
RFs (5)
- age
- smoking
- white or chinese ethnicity
- FH
- CVS disease
Age Related Macular Degeneration
presentation (3)
- gradual worsening central visual field loss
- reduced visual acuity
- crooked or waxy appearance to straight lines
Age Related Macular Degeneration
difference in presentation of wet and dry AMD
wet is more acute
loss of vision over days and progress to full loss of vision over 2-3 years.
often progresses to bilateral disease.
Age Related Macular Degeneration
examination + inx findings
- Snellen chart: reduced acuity
- Scotoma: central patch of vision loss
- Amsler grid test: distortion of straight lines
- Fundoscopy: drusen
- Slit-lamp biomicroscopic fundus examination
- Optical coherence tomography
- Fluorescein angiography
Age Related Macular Degeneration
dx with what
Slit-lamp biomicroscopic fundus examination by a specialist
Age Related Macular Degeneration
what is Optical coherence tomography
a technique used to gain a cross-sectional view of the layers of the retina.
can be used to diagnose wet AMD.
Age Related Macular Degeneration
what is Fluorescein angiography
involves giving a fluorescein contrast and photographing the retina to look in detail at the blood supply to the retina
useful to show up any oedema and neovascularisation
used 2nd line to diagnose wet AMD
Age Related Macular Degeneration
mnx of dry AMD
refer to ophthalmologist
- Avoid smoking
- Control blood pressure
- Vitamin supplementation
Age Related Macular Degeneration
mnx of wet AMD
Anti-VEGF medications:
ranibizumab, bevacizumab and pegaptanib block VEGF and slow the development of new vessels
need to be started within 3m to be beneficial
Age Related Macular Degeneration
how often are Anti-VEGF medication injected
once a month injected directly into the vitreous chamber
Diabetic Retinopathy
what is it
condition where the blood vessels in the retina are damaged by prolonged exposure to high blood sugar levels
causing a progressive deterioration in the health of the retina
Diabetic Retinopathy
pathophysiology : hyperglycaemia leads to…
hyperglycaemia –> damage to retinal small vessels + endothelial cells
Diabetic Retinopathy
pathophysiology: increased vascular permeability leads to ….
leakage from blood vessels, blot haemorrhages and the formation of hard exudates (yellow/white deposits of lipids in the retina)
Diabetic Retinopathy
pathophysiology: damage to blood vessel walls lead to
microaneurysms: weakness in the wall causes small bulges
and venous beading: walls of the veins are no longer straight and parallel and look more like a string of beads or sausages
Diabetic Retinopathy
pathophysiology: damage to nerve fibres in the retina causes..
cotton wool spots: fluffy white patches formed on the retina
Diabetic Retinopathy
pathophysiology: what is intraretinal microvascular abnormalities (IMRA)
where there are dilated and tortuous capillaries in the retina
these can act as a shunt between the arterial and venous vessels in the retina
Diabetic Retinopathy
pathophysiology: what is neovascularisation
when growth factors are released in the retina causing the development of new blood vessels
Diabetic Retinopathy
how can diabetic retinopathy be split into
- non-proliferative
- proliferative
- diabetic maculopathy
depending on whether new blood vessels have developed
Diabetic Retinopathy
mild non-proliferative diabetic retinopathy
microaneurysms
Diabetic Retinopathy
moderate non-proliferative diabetic retinopathy
- microaneurysms
- blot haemorrhages
- hard exudates
- cotton wool spots
- venous beading
Diabetic Retinopathy
severe non-proliferative diabetic retinopathy
- blot haemorrhages + microaneurysms in 4 quadrants
- venous beading in 2 quadrants
- intraretinal microvascular abnormality (IMRA) in any quadrant
Diabetic Retinopathy
proliferative diabetic retinopathy (2)
- neovascularisation
- vitreous haemorrhage
Diabetic Retinopathy
diabetic maculopathy (2)
- macular oedema
- ischaemic maculopathy
Diabetic Retinopathy
complications (5)
- retinal detachment
- vitreous haemorrhage
- Rebeosis iridis
- Optic neuropathy
- Cataracts
Diabetic Retinopathy
complications: what are vitreous heamorrhages
bleeding into the vitreous humour
Diabetic Retinopathy
complications: what is Rebeosis iridis
new blood vessel formation in the iris
Diabetic Retinopathy
mnx
- laser photocoagulation
- anti-VEGF meds: ranibizumab, bevacizumab
- vitreoretinal surgery: keyhole surgery on the eye may be required in severe disease
Cataracts
what is it
where the lens becomes cloudy and opaque
this reduces visual acuity by reducing the light that enters the eye
Cataracts
what is the lens’ function
to focus light coming into the eye onto the retina at the back of they eye
Cataracts
what is the lens held in place by
suspensory ligaments attached to the ciliary body
Cataracts
how does the lens thicken
when the ciliary body contracts it releases tension on the suspensory ligaments and the lens thicken
Cataracts
how does the lens narrow
when the ciliary body relaxes it increases the tension in the suspensory ligaments and the lens narrows
Cataracts
how is the lens nourished
by the surrounding fluid, it doesn’t have a blood supply
Cataracts
how is congenital cataracts screened for
using the red reflex during the neonatal examination
Cataracts
RFs (6)
- increasing age
- smoking
- alcohol
- diabetes
- steroids
- hypocalcaemia
Cataracts
presentation
- usually asymmetrical
- very slow reduction in vision
- progressive blurring of vision
- change in colour of vision: colours more brown or yellow
- ‘starbursts’ can appear around lights esp at night
Cataracts
key sign
loss of the red reflex
Cataracts
mnx if symptoms are manageable
no intervention
Cataracts
mnx
cataract surgery
Cataracts
what does cataract surgery involve
drilling and breaking the lens into pieces, removing the pieces
then implanting an artificial lens into the eye
Cataracts
why might the pt still have poor visual acuity after cataract surgery
other pathology may be detected after surgery as cataracts can prevent the detection beforehand
Cataracts
what is a rare but serious complication of cataract surgery
Endophthalmitis
Cataracts
what is endophthalmitis
rare but serious complication of cataract surgery
inflammation of the inner contents of the eye, usually caused by infection
Cataracts
how can endophthalmitis be treated
with intravitreal antibiotics injected into the eye
Conjunctivitis
what is the conjunctiva
a thin layer of tissues that covers the inside of eyelids and the sclera of the eye
Conjunctivitis
what are the 3 types
- bacterial
- viral
- allergic
Conjunctivitis
presentation
- unilateral or bilateral
- red eyes
- bloodshot
- itchy or gritty sensation
- discharge from the eye
Conjunctivitis
does it cause pain, photophobia or reduced visual acuity?
NO
Conjunctivitis
how does bacterial conjunctivits present
purulent discharge
inflamed conjunctiva
worse in morning when eyes may be stuck together
starts in 1 eye and spread to other
Conjunctivitis
how does viral conjunctivitis present
clear discharge
other sx of a viral infection
tender preauricular lymph nodes
Ddx for painless red eye
- conjunctivitis
- episcleritis
- subconjunctival haemorrhage
Ddx for painful red eye
- glaucoma
- anterior uveitis
- scleritis
- corneal abrasions or ulceration
- keratitis
- foreign body
- traumatic or chemical injury
Conjunctivitis
mnx
usually resolves within 1-2w
good hygiene: avoid sharing towels, wash hands, avoid contacts, clean eyes with hot water
Conjunctivitis
when can antibiotic eye drops be considered
in bacterial conjunctivitis: chloramphenicol and fuscidic acid
Conjunctivitis
why do pts <1y need urgent ophthalmology review
neonatal conjunctivits can be associated with gonococcal infection
and can cause loss of sight and more severe complications such as pnuemonia
Conjunctivitis
what is allergic conjunctivitis caused by
contact with allergens
Conjunctivitis
what does allergic conjunctivitis present as
- swelling of conjunctival sac and eye lid
- significant watery discharge and itch
Conjunctivitis
trx for allergic conjunctivitis
oral or topical antihistamines
topical mast-cell stabiliser if chronic seasonal sx
Conjunctivitis
how do mast-cell stabiliser work
preventing mast cells releasing histamine
Anterior Uveitis
what is it
inflammation in the anterior part of the uvea
aka iritis
Anterior Uveitis
what does the uvea involve
- iris
- ciliary body
- choroid
Anterior Uveitis
what is the choroid
the layer between the retina and sclera all the way around the eye
Anterior Uveitis
pathophysiology
- inflammation and immune cells in the anterior chamber of the eye
- the anterior chamber of the eye becomes infiltrated by neutrophils, lymphocytes and macrophages
- usually caused by an autoimmune process but can be due to infection, trauma, ischaemia or malignancy
Anterior Uveitis
what causes floaters in the pt’s vision
inflammatory cells in the anterior chamber
Anterior Uveitis
what types are there
acute or chronic
Anterior Uveitis
difference between acute and chronic
chronic: more granulomatous (has more macrophages) and has a less severe and longer duration of symptoms, lasting >3m
Anterior Uveitis
what is acute anterior uveitis associated with
HLA B27 conditions:
- ankylosing spondylitis
- IBD
- Reactive arthritis
Anterior Uveitis
what is chronic anterior uveitis associated with
- sarcoidosis
- syphilis
- lyme disease
- TB
- herpes virus
Anterior Uveitis
presentation
- unilateral
- may occur with a flare of reactive arthritis
- dull, aching, painful red eye
- ciliary flush
- miosis
- photophobia
- pain on movement
- lacrimation
- abnormally shaped pupil
- hypopyon
Anterior Uveitis
what is ciliary flush
a ring of red spreading from the cornea outwards
Anterior Uveitis
what causes miosis
sphincter muscle contraction
Anterior Uveitis
what causes photophobia
ciliary muscle spasm
Anterior Uveitis
what causes an abnormal shaped pupil
posterior synechiae (adhesions) pulling the iris into abnormal shapes
Anterior Uveitis
what is hypopyon
a collection of WBCs in the anterior chamber, seen as a yellowish fluid collection settled in front of the lower iris with a fluid level
Anterior Uveitis
NICE guidelines on pts with potentially sight threatening causes of red eye
refer for same day assessmentt by ophthalmologist
full slit lamp assessment and intraocular pressures
Anterior Uveitis
trx choices
- steroids (PO, top, IV)
- cycloplegic-mydriatic meds: cyclopentolate or atropine eye drops
- immunosuppresants: DMARDS and TNF inhibitors
- laser therapy, cryotherapy, vitrectomy for severe cases
Anterior Uveitis
what does cycloplegic mean
paralysing the ciliary muscles
Anterior Uveitis
what does mydriatic mean
dilating the pupils
Anterior Uveitis
how do cyclopentolate and atropine work
antimuscarinics that block the action of iris sphincter muscles and ciliary body
these dilate the pupil and reduce pain associated with ciliary spasm by stopping the action of the ciliary body
Retinal Detachment
what is it
where the retina separates from the choroid underneath
usually due to a retinal tear that allows vitreous fluid to get under the retina and fill the space between the retina and choroid
Retinal Detachment
what makes it a sight-threatening emergency
the outer retina relies on the blood vessels of the choroid for its blood supply
Retinal Detachment
RFs(6)
- posterior vitreous detachment
- diabetic retinopathy
- trauma to the eye
- retinal malignancy
- older age
- FH
Retinal Detachment
presentation (3)
- peripheral vision loss. Often sudden and like a shadow coming across the vision
- blurred or distorted vision
- flashes and floaters
Retinal Detachment
presents with painless flashes and floaters. Mnx?
detailed assessment of retina to detect retinal tears or detachment
immediately refer to ophthalmology
Retinal Detachment
mnx of retinal tears
aim to create adhesions between the retina and choroid to prevent detachment
- laser therapy
- cryotherapy
Retinal Detachment
mnx options for reattaching the retina
- vitrectomy
- scleral buckling
- pneumatic retinopexy
Retinal Detachment
what does vitrectomy involve
removing the relevant parts of the vitreous body and replacing it with oil or gas
Retinal Detachment
what does scleral buckling involve
using a silicon ‘buckle’ to put pressure on the outside of the eye (the sclera) so that the outer indents bring the choroid inwards and into contact with the detached retina
Retinal Detachment
what does pneumatic retinopexy involve
injecting a gas bubble into the vitreous body and positioning the patient so the gas bubble creates pressure that flattens the retina against the choroid and close the detachment.
Blepharitis
what is it
inflammation of the eyelid margins
Blepharitis
presentation
gritty, itchy, dry sensation in the eyes
Blepharitis
what can it be associated with
dysfunction of the Meibomian glands, which are responsible for secreting oil onto the surface of the eye
can lead to styes and chalazions
Blepharitis
mnx
- hot compresses
- gentle cleaning of the eyelid margins to remove debris using cotton wool dipped in sterilised water + baby shampoo
- lubricating eye drops to relieve symptoms
Blepharitis
what lubricating eye drop is usually started with
Polyvinyl alcohol
the middle viscous choice
Blepharitis
which lubricating eye drop is the least viscous and how long does it last for
Hypromellose
least viscous lasting around 10 min
Blepharitis
which lubricating eye drop is the most viscous and how long does it last for
Carbomer
most viscous and lasts 30-60min
Stye
what is Hordeolum externum
an infection of the glands of Zeis or glands of Moll
Stye
what are the glands of Zeis
sebaceous glands at the base of the eyelashes
Stye
what are the glands of Moll
sweat glands at the base of the eyelashes
Stye
presentation
tender red lump along the eyelid that may contain pus
Stye
what is Hordeolum internum
infection of the Meibomian glands
deeper, more painful
may point inwards towards the eyeball underneath the eyelid
Stye
trx
hot compresses and analgesia
consider topical abx (i.e. chloramphenicol) if assc w/ conjunctivitis or persistent
Chalazion
when does it occur
when a Meibomian gland becomes blocked and swells up
Chalazion
aka?
Meibomian cyst
Chalazion
presentation
swelling in the eyelid
typically not tender
but can be tender and red
Chalazion
trx
hot compress and analgesia
consider topical abx (i.e. chloramphenicol) if acutely inflamed
surgical drainage may be required
Entropion
what is it
where the eyelid turns inwards with the lashes against the eyeball
Entropion
what does it result in
pain and corneal damage and ulceration
Entropion
initial mnx
tape eyelid down to prevent it turning inwards
+ regular lubricating eye drops to prevent eye drying out
Entropion
definitive mnx
surgical intervention
Entropion
when to refer to ophthalmology same day
if there is a risk to sight
Ectropion
what is it
where the eyelid turns outwards with the inner aspect of the eyelid exposed
usually affects the bottom lid
Ectropion
what can it lead to and why
exposure keratopathy as the eyeball is exposed and not adequately lubricated and protected
Ectropion
trx
mild: none
regular lubricating eye drops
severe: surgery
Trichiasis
what is it
inward growth of the eyelashes
results in pain, corneal damage and ulceration
Trichiasis
mnx
epilation (remove eyelash)
Trichiasis
recurrent cases mnx
electrolysis, cryotherapy or laser trx to prevent the lash regrowing
Periorbital Cellulitis
what is it
eyelid and skin infection in the front of the orbital septum (in front of the eye)
Periorbital Cellulitis
presentation
swelling, redness and hot skin around the eyelids and eye
Periorbital Cellulitis
Ddx
orbital cellulitis ! a sight and life threatening emergency
Periorbital Cellulitis
how to distinguish between periorbital and orbital cellulitis
CT scan
Periorbital Cellulitis
trx
systemic abx (PO or IV)
vulnerable pts or sever may require admission as can develop into orbital cellulitis
Orbital Cellulitis
what is it
infection around the eyeball that involves tissues behind the orbital septum.
Orbital Cellulitis
key features that differentiate this from periorbital cellulitis
- pain on eye movement
- reduced eye movements
- changes in vision
- abnormal pupil reactions
- proptosis (forward movement of the eyeball)
Orbital Cellulitis
mnx
medical emergency that requires admission and IV antibiotics
may require surgical drainage if an abscess forms.
Subconjunctival Haemorrhage
what is it
one of the small blood vessels within the conjunctiva ruptures and release blood into the space between the sclera and the conjunctiva
Subconjunctival Haemorrhage
what activities may it occur after
episodes of strenuous activity such as heavy coughing, weigh lifting or straining when constipated
or trauma to the eye
Subconjunctival Haemorrhage
what conditions may have contributed to it
- HTN
- bleeding disorders (e.g. thrombocytopenia)
- whooping cough
- medications (warfarin, NOACs, antiplatelets)
- non-accidental injury
Subconjunctival Haemorrhage
presentation
- patch of bright red blood underneath the conjunctiva and in front of the sclera covering the white of the eye
- painless, doesn’t affect vision
Subconjunctival Haemorrhage
dx
hx and examination
Subconjunctival Haemorrhage
mnx
2w to resolve spontaneously
possible causes: HTN, bleeding disorders may need further inx
Subconjunctival Haemorrhage
if there is a foreign body sensation, what can help
lubricating eye drops
Retinal Vein Occlusion
where does the central retinal vein run through
the optic nerve
Retinal Vein Occlusion
what is the central retinal vein responsible for
draining blood from the retina
Retinal Vein Occlusion
what is central retinal vein occlusion
thrombus forms in the retinal veins and blocks the drainage of blood from the retina
Retinal Vein Occlusion
how many branched veins come together to form the central retinal vein
4
Retinal Vein Occlusion
what does blockage of one of the branched vein cause
problems in the area drained by that branch
Retinal Vein Occlusion
what does blockage in the central vein cause
problems with the whole retina
Retinal Vein Occlusion
symptom
sudden painless loss of vision
Retinal Vein Occlusion
what inx is diagnostic
fundoscopy
Retinal Vein Occlusion
what does fundoscopy show
- flame and blot haemorrhages
- optic disc oedema
- macula oedema
Retinal Vein Occlusion
why is there macula oedema and retinal haemorrhages
blockage of retinal vein causes pooling of blood in the retina
this results in leakage of fluid and blood
Retinal Vein Occlusion
what do macula oedema and retinal haemorrhages lead to
damage to the tissue in the retina and loss of vision
also leads to the release of VEGF which stimulates the development of new blood vessels (neovascularisation)
Retinal Vein Occlusion
RFs (6)
- HTN
- high cholesterol
- diabetes
- smoking
- glaucoma
- SLE
Retinal Vein Occlusion
inx to check for possible associated conditions
- full medical hx
- FBC: leukaemia
- ESR: inflammatory disorders
- BP
- serum glucose
Retinal Vein Occlusion
should you refer
yes if suspected, refer immediately to ophthalmologist
Retinal Vein Occlusion
mnx
- laser photocoagulation
- intravitreal steroids (dexamethasone intravitreal implant)
- anti-VEGF therapies (ranibizumab, aflibercept or bevacizumab)
Retinal Vein Occlusion
what is the aim of mnx
to treat macular oedema and prevent complications such as neovascularisation of the retina and iris and glaucoma
Central Retinal Artery Occlusion
what supplies the blood to the retina
the central retinal artery
Central Retinal Artery Occlusion
what is the central retinal artery a branch of
the ophthalmic artery, which is a branch of the internal carotid artery
Central Retinal Artery Occlusion
most common cause
atherosclerosis
can also be caused by GCA
Central Retinal Artery Occlusion
how does giant cell arteritis cause it
vasculitis affecting the ophthalmic or central retinal artery causes reduced blood flow
Central Retinal Artery Occlusion
RFs
the same for CVD:
- older age
- FH
- Smoking
- alcohol
- hypertension
- diabetes
- poor diet
- inactivity
- obesity
Central Retinal Artery Occlusion
main presentation
sudden painless loss of vision
Central Retinal Artery Occlusion
what is relative afferent pupillary defect
the pupil in the affected eye constricts more when light is shone in the other eye compared when it is shone in the affected eye
Central Retinal Artery Occlusion
why does relative afferent pupillary defect occur
because the input is not being sensed by the ischaemic retina when testing the direct light reflex
but is being sensed by the normal retina during the consensual light reflex
Central Retinal Artery Occlusion
what will fundoscopy show
a pale retina
with a cherry-red spot
Central Retinal Artery Occlusion
why is the retina pale
due to a lack of perfusion with blood
Central Retinal Artery Occlusion
what is the cherry-red spot on fundoscopy
the macula, which has a thinner surface that shows the red coloured choroid below and contrasts with the pale retina
Central Retinal Artery Occlusion
mnx
refer immediately
if suspecting GCA: ESR, temporal artery biopsy , high dose steroids
Central Retinal Artery Occlusion
immediate mnx
- ocular massage
- remove fluid from anterior chamber to reduce intraocular pressure
- inhale carbogen (5% CO2 + 95% O2) to dilate artery
- sublingual isosorbide dinitrate to dilate the artery
Central Retinal Artery Occlusion
long term mnx
treat reversible RFs and secondary prevention of CVD
Posterior Vitreous Detachment
what is the vitreous body
the gel inside the eye that maintains the structure of the eyeball and keeps the retina pressed on the choroid
Posterior Vitreous Detachment
what is the vitreous body made of
collagen and water
Posterior Vitreous Detachment
what is it
the vitreous gel comes away from the retina
very common, esp in older pts
Posterior Vitreous Detachment
presentation
- painless
- spots of vision loss
- floaters
- flashing lights
presents similarly to retinal tear/detachment
Posterior Vitreous Detachment
mnx
none, over time the sx will improve as the brain adjusts
Posterior Vitreous Detachment
what are pts predisposed to
retinal tears and retinal detachment
Herpes Keratitis
what is keratitis
inflammation of the cornea
causes of keratitis
- viral: herpes simplex
- bacterial: pseudomonas or staph
- fungal: candida or aspergillus
- contact lens acute red eye
- exposure karatitis
what is the most common cause of keratitis
herpes simplex keratitis
Herpes Keratitis
what layer does herpes keratitis usually only affect
the epithelial layer of the cornea
Herpes Keratitis
what is stromal keratitis
if there is inflammation of the stroma (the layer between the epithelium and endothelium)
Herpes Keratitis
what is stromal keratitis associated with
complications such as stromal necrosis, vascularisation and scarring and can lead to corneal blindness
Herpes Keratitis
presentation
- painful red eye
- photophobia
- vesicles around the eye
- foreign body sensation
- watering eye
- reduced visual acuity
Herpes Keratitis
what will staining with fluorescein show
dendritic corneal ulcer
Herpes Keratitis
what is required to find and diagnose keratitis
slit lamp
Corneal swabs or scrapings can be used to isolate the virus using a viral culture or PCR.
Herpes Keratitis
mnx
- Aciclovir (topical or oral)
- Ganciclovir eye gel
- Topical steroids may be used alongside antivirals to treat stromal keratitis
Herpes Keratitis
trx for corneal scarring caused by stromal keratitis
a corneal transplant may be required
Scleritis
what is the most severe type
necrotising scleritis: visual impairment but may not have pain
Scleritis
what is the most significant complication
perforation of the sclera
Scleritis
what are some associated systemic conditions
- RA
- SLE
- IBD
- Sarcoidosis
- Granulomatosis w/ polyangiitis
Scleritis
presentation
- acute severe pain
- pain w/ eye movement
- photophobia
- eye watering
- reduced visual acuity
- abnormal pupil reaction to light
- tenderness to palpation of the eye
Scleritis
mnx
- NSAIDs
- Steroids
- Immunosuppression for underlying systemic condition
Episcleritis
what is it
benign and self-limiting inflammation of the episclera, the outermost layer of the sclera.
Episcleritis
whom is it common in
young and middle-aged adults
Episcleritis
which inflammatory disorders is it associated with
RA and IBD
Episcleritis
presentation
- acute + unilateral
- no pain
- segmental redness
- foreign body sensation
- dilated episcleral vessels
- watering of eye
- no discharge
Episcleritis
mnx
- recovers in 1-4w
- analgesia
- cold compresses
- lubricating eye drops
Pupil Disorders
what causes pupil constriction
parasympathetic nervous system using ACh contracts circular muscles in the iris which cause pupil constriction
travels along CN III (oculomotor)
Pupil Disorders
what causes pupil dilation
dilator muscles stimulated by the sympathetic NS using adrenalin as a neurotransmitter
Pupil Disorders
what can cause trauma to the sphincter muscles in the iris
cataract surgery and other eye operations causing an irregular pupil
Pupil Disorders
how can anterior uveitis cause misshapen pupils
can cause adhesions in the iris
Pupil Disorders
what can cause a vertical oval pupil
Acute angle closure glaucoma can cause ischaemic damage to the muscles of the iris
Pupil Disorders
what is Rubeosis iridis
neovascularisation in the iris can distort the shape of the iris and pupil.
usually associated with poorly controlled diabetes and diabetic retinopathy.
Pupil Disorders
what is Coloboma
congenital malformation in the eye.
This can cause a hole in the iris causing an irregular pupil shape.
Pupil Disorders
what is tadpole pupil
spasm in a segment of the iris causing a misshapen pupil.
usually temporary and associated with migraines.
Pupil Disorders
causes of mydriasis (dilated pupil)
- 3rd nerve palsy
- Holmes-Adie syndrome
- raised ICP
- congenital
- trauma
- stimulants: cocaine
- anticholinergics
Pupil Disorders
causes of miosis (constricted pupil)
- Horner’s syndrome
- cluster headaches
- Argyll-Robertson pupil (in neurosyphilis)
- opiates
- nicotine
- pilocarpine
Pupil Disorders
3 signs in 3rd nerve palsy
- divergent strabismis: down + out
- ptosis
- dilated non-reactive pupil
Pupil Disorders
what does the 3rd nerve (oculomotor) supply
all of the extraocular muscles except the lateral rectus and superior oblique: down + out
levator palpebrae superioris: ptosis
sphincter muscle of the iris: dilated fixed pupil
Pupil Disorders
how can a cavernous sinus thrombosis and posterior communicating artery aneurysm cause compression of the 3rd nerve, causing palsy
the oculomotor nerve travels from the brainstem through the cavernous sinus and close to the posterior communicating artery
Pupil Disorders
what does a 3rd nerve palsy with sparing of the pupil suggest
a microvascular cause as the parasympathetic fibres are spared. May be due to:
- DM
- HTN
- ischaemia
Pupil Disorders
what is a full 3rd nerve palsy (surgical 3rd) cause
compression of the 3rd nerve inc the parasympathetic fibres
Pupil Disorders
what is a full 3rd nerve palsy due to
- Idiopathic-
- Tumour
- Trauma
- Cavernous sinus thrombosis
- Posterior communicating artery aneurysm
- Raised ICP
Pupil Disorders
Horner syndrome triad
- ptosis
- miosis
- anhidrosis (loss of sweating)
Pupil Disorders
Horner syndrome cause
damage to the sympathetic nervous system supplying the face.
Pupil Disorders
Horner syndrome: journey of the sympathetic nerves
- spinal cord in chest (pre-ganglionic nerves)
- enter into the sympathetic ganglion at the base of the neck
- exit as post-ganglionic nerves
- then travel to the head, running alongside the internal carotid artery.
Pupil Disorders
location of Horner’s syndrome if there is anhidrosis of the arm, trunk and face
central lesions (4 Ss):
- Stroke
- MS
- Swelling (tumour)
- Syringomyelia (cyst in the spinal cord)
Pupil Disorders
location of Horner’s syndrome if there is anhidrosis in the face only
Pre-ganglionic lesions (4 Ts):
- Pancoast’s tumour
- Trauma
- Thyroidectomy
- Top rib: a cervical rib growing above the first rib above the clavicle
Pupil Disorders
location of Horner’s syndrome if no anhidrosis
Post-ganglionic lesions (4 Cs)
- Carotid aneurysm
- Carotid artery dissection
- Cavernous sinus thrombosis
- Cluster headache
Pupil Disorders
what is Congenital Horner syndrome associated with
heterochromia: difference in the colour of the iris on the affected side.
Pupil Disorders
what test can be used for Horner Syndrome
Cocaine eye drops/Apraclonidine
or
adrenalin eye drop (0.1%)
Pupil Disorders
how does cocaine eye drops test for Horner’s syndrome
Cocaine acts on the eye to stop noradrenalin re-uptake at the neuromuscular junction
normal eye dilates because there is more noradrenalin stimulating the dilator muscles of the iris
Horner: the nerves are not releasing noradrenalin to start with so blocking re-uptake does not make a difference and there is no reaction of the pupil
Pupil Disorders
results of adrenalin eye drop (0.1%) test for Horner’s syndrome
normal: won’t dilate
horner: dilates
Pupil Disorders
what is Holmes Adie Pupil
unilateral dilated pupil that is sluggish to react to light with slow dilation of the pupil following constriction
Over time the pupil will get smaller
Pupil Disorders
what is Holmes Adie pupil caused by
damage to the post-ganglionic parasympathetic fibres. The exact cause is unknown but may be viral.
Pupil Disorders
what is Holmes Adie Syndrome
Holmes Adie pupil with absent ankle and knee reflexes.
Pupil Disorders
what is Argyll-Robertson Pupil
specific finding in neurosyphilis
constricted pupil that accommodates when focusing on a near object but does not react to light. They are often irregularly shaped
Pupil Disorders
what is Argyll-Robertson Pupil often called and why
“prostitutes pupil” due to the relation to neurosyphilis and because “it accommodates but does not react“.
Retinitis Pigmentosa
what is it
congenital inherited condition
degeneration of the rods and cones in the retina
Retinitis Pigmentosa
when do most cases start
in childhood
Retinitis Pigmentosa
presentation
1st symptom: night blindness
peripheral vision is lost before central vision
Retinitis Pigmentosa
why is night blindness the first symptom
the rods degenerate more than cones
Retinitis Pigmentosa
what will fundoscopy show
“bone-spicule” pigmentation
Retinitis Pigmentosa
what does “bone-spicule” pigmentation mean
spicule: sharp, pointed
Bone-spicule is used to refer to the similarity to the networking appearance of bone matrix.
Retinitis Pigmentosa
associated systemic diseases
- Usher’s Syndrome: hearing loss + retinitis pigmentosa
- Bassen-Kornzweig Syndrome: disorder of fat absorption + metabolism causing progressive neuro sxs and retinitis pigmentosa
- Refsum’s Disease: metabolic disorder of phytanic acid causing neuro, hearing and skin sxs and retinitis pigmentosa
Retinitis Pigmentosa
general mnx
- refer to ophthalmologist
- genetic counselling
- vision aids
- sunglasses
- inform DVLA
- follow up regularly
Retinitis Pigmentosa
medical mnx which may be considered
- Vitamin and antioxidant supplements
- PO acetazolamide
- Topical dorzolamide
- Steroid injections
- Anti-VEGF injections
Corneal Abrasions
common causes
- contact lenses
- foreign bodies
- finger nails
- eyelashes
- entropion (inward turning eyelid)
Corneal Abrasions
what organism is associated with use of contact lenses
pseudomonas
Corneal Abrasions
important differential
herpes keratitis: needs antiviral eye drops
Corneal Abrasions
presentation
- History of contact lenses or foreign body
- Painful red eye
- Foreign body sensation
- Watering eye
- Blurring vision
- Photophobia
Corneal Abrasions
dx
fluorescein stain highlights abrasions or ulcers
slit lamp for more significant abrasions
Corneal Abrasions
mnx
- refer immediately if sight threatening cause of red eye
- Simple analgesia (e.g. paracetamol)
- Lubricating eye drops can improve symptoms
- Antibiotic eye drops (i.e. chloramphenicol)
- review in 1w to check it has healed
- Cyclopentolate eye drops dilate the pupil and improve significant symptoms, particularly photophobia.
- Uncomplicated corneal abrasions usually heal over 2-3 days.
Hypertensive Retinopathy
what is it
damage to the small blood vessels in the retina relating to systemic hypertension
Hypertensive Retinopathy
cause
- years of chronic hypertension
- or it can develop quickly in response to malignant hypertension
Hypertensive Retinopathy
signs in the eye
- silver/copper wiring
- arteriovenous nipping
- cotton wool spots
- hard exudates
- retinal haemorrhages
- papilloedema
Hypertensive Retinopathy
signs: what is silver or copper wiring
the walls of the arterioles become thickened and sclerosed causing increased reflection of the light
Hypertensive Retinopathy
signs: what is arteriovenous nipping
sclerosis and hardening of the arterioles cause compression of the veins where they cross.
Hypertensive Retinopathy
signs: what causes cotton wool spots
ischaemia and infarction in the retina causing damage to nerve fibres
Hypertensive Retinopathy
signs: what are hard exudates caused by
damaged vessels leaking lipids into the retina
Hypertensive Retinopathy
signs: what are retinal haemorrhages caused by
damaged vessels rupturing and releasing blood into the retina
Hypertensive Retinopathy
signs: what is papilledema caused by
ischaemia to the optic nerve resulting in optic nerve swelling (oedema) and blurring of the disc margins
Hypertensive Retinopathy
Stage 1 Keith-Wagener Classification
Mild narrowing of the arterioles
Hypertensive Retinopathy
Stage 2 Keith-Wagener Classification
Focal constriction of blood vessels and AV nicking
Hypertensive Retinopathy
Stage 3 Keith-Wagener Classification
Cotton-wool patches, exudates and haemorrhages
Hypertensive Retinopathy
Stage 4 Keith-Wagener Classification
Papilloedema
Hypertensive Retinopathy
mnx
- control BP
- control RFs: smoking, blood lipid levels
what is trachoma
a bacterial keratoconjunctivitis caused by Chlamydia trachomatis
who is trachoma common in
children and adults with poor hygiene e.g, in resource poor areas of the world.
presentation of trachoma
- conjunctival scarring and corneal abrasion
trx of trachoma
typically Azithromycin as a one-off dose
what is a common finding in acute ischaemic optic neuropathy
swollen optic disc
what is ophthalmia neonatorum
aka neonatal conjunctivitis
an infection of the conjunctiva contracted by neonates within the first 28 days following birth
sx of ophthalmia neonatorum
hyperaemia, swollen eyelids, conjunctival discharge and chemosis
what is chemosis
oedema of the conjunctiva
what are the 2 most common causes of ophthalmia neonatorum
chlamydia and gonorrhoea
difference between chlamydia and gonorrhoea conjunctivitis
Gonococcal:
- commonly presents from 0-3d following birth
- purulent discharge
Chlamydial:
- commonly presents from 5d onwards following birth
- mucopurulent discharge
‘A single, well demarcated white ulcer’
what is it
bacterial keratitis
‘Vertical linear defects in the corneal epithelium’
what is it
corneal abrasion
represents the damage caused every time the patient blinks due to a foreign object
what is the Ishihara plate score
test for determining colour vision deficiency
how would acute optic neuropathy present as (4)
- central scotoma
- Reduced colour vision
- Relative afferent pupillary defect
- Acutely: optic disc swelling;
chronically, with death of optic nerve fibres: atrophy (seen as a pale disc)
Ddx of optic neuropathy (5)
- Demyelinating (MS associated) optic neuritis -
- Ischaemic optic neuropathy (eg GCA)
- Compression (eg optic nerve glioma, metastatic tumour)
- Nutrition: B12/folate deficiency, alcohol excess - usually bilateral, symmetrical (thus no RAPD)
- Raised ICP, malignant hypertension, sarcoid, ethambutol
trx of gonococcal conjunctivitis
- IV Ceftriaxone
- bacitracin ointment
- hourly saline lavage
what is ciliary injection
involves branches of the anterior ciliary arteries and indicates inflammation of the cornea, iris, or ciliary body.
6-hour history of dull pain in his right eye.
O/E: eye appears red, cornea is cloudy and there is evidence of ciliary injection
what is it
acute angle closure glaucoma.
what is the definitive test for diagnosing acute angle closure glaucoma
Gonioscopy: using goniolens + slit lamp in to gain a view of the angle between the eye’s cornea and iris
what is a strong indicator of ocular involvement in Herpes Zoster Ophthalmicus
Hutchinson’s sign: A skin lesion on the tip or side of the nose
Small penetrating objects can often leave a sealed wound and may not be visible clinically. what imaging is required?
urgent CT scan
mnx if a foreign body is found on CT scan
urgent surgery to close the wound and remove the foreign body
what medication may raise IOP
Topical steroids, steroid eye drops, and systemic steroids
causes of Horner’s syndrome
Pancoast tumour (affecting sympathetic nerve supply)
Stroke
Carotid artery dissection (Red flag: neck pain)
describe a keratocanthoma
A rapidly growing, well differentiated lesion that is “dome shaped” in appearance
central depression and debris within
painless
can be on eyelid
what is a retinoblastoma
a malignant tumour of the retina, and the most common intraocular tumour of childhood
presentation of retinoblastoma
- leukocoria (white pupil)
- deteriorating vision
- strabismus
- failure to thrive
fundoscopy shows a stormy sunset. What is it
Central retinal vein occlusion
difference on examination with Argyll-Robertson pupil or Holmes-Adie tonic pupil
Holmes-Adie: after the patient is asked to accommodate, the dilated pupil tones up, so much so that it becomes smaller compared to the other pupil (ie the anisocoria is reversed)
Argyll-Robertson: some constriction will be seen, but the pathological pupil will remain bigger compared to the other
mnx of Holmes-Adie
reassure
is long sightedness a RF for acute angle glaucoma
yes
mnx for idiopathic intracranial hypertension
Acetazolamide
mannitol would cause a fluid shift too rapidly
when is contrast used in CT
- to see if normal blood vessels have become blocked (PE or ischaemic stroke)
- to see if abnormal structures have developed new blood supplies (ie neovascularisation surrounding a malignancy)
punched in eye proptosis severe pain restricted eye movement rapid deterioration in vision
what is it
retrobulbar haemorrhage, leading to orbital compartment syndrome
mnx of orbital compartment syndrome
urgent decompression by lateral canthotomy
when would you give anti-VEGF vs photocoagulation in diabetes
anti-VEGF: clinically significant diabetic macular oedema
photocoagulation: proliferative diabetic retinopathy
most common cause of surgical 3rd nerve palsy
posterior communicating artery aneurysm.
Other causes: cavernous sinus lesions (infection, thrombosis, tumour infiltration).
which therapy is contraindicated in thyroid eye disease
Radioactive iodine ablation therapy
is plasma copper high or low in wilson’s disease
low
because it quickly accumulates in the liver and the CNS
A patient with signs of an oculomotor nerve palsy (cranial nerve 3) with pupillary signs (mydriasis) should be assumed to have?
an aneurysm of their ipsilateral posterior communicating artery until proven otherwise
what inx for a retinal tear if cannot view retina because of a vitreous haemorrhage
A B-scan ultrasound will help determine if the retina has detached as it is not possible to view this patient’s retina.
eye cannot look out away from the nose. What palsy is it
6th nerve palsy
eye is upwards and inwards and the patient may present with a tilted head. What palsy is it
4th nerve palsy
painful red nodule on her left lower eyelid.
lesion has a pearly margin with an ulcerated centre. What is the most likely diagnosis?
Basal cell carcinoma
12m old baby has large cream coloured mass in the fundus of both eyes.
The red reflex is absent. What is it
Hereditary retinoblastoma
Fundoscopy reveals a large yellow lesion at the back of the eye. 40 pack smoker
what is it
Ocular metastases
6-month-old child with a 5-month history of a rapidly growing bright red lesion on his right upper eyelid.
the right upper eyelid bisects the pupil and the lesion blanches on pressure
what is it
large haemangioma
trx of a large haemangioma obstructing vision
PO propranolol
difference between surgical and medical 3rd nerve palsy
surgical: pupil is dilated
double vision that is worse particularly when looking down and gets better when tilting his head to the right side. He particularly struggles to walk down stairs. what is it
Left fourth-nerve palsy
where is the likely source of infection if she has orbital cellulitis involving the ocular muscles and causing compression of the optic nerve
the ethmoid sinus
sits medially to the orbit
pain started last night when he accidentally scratched his eye while taking his contact lens out. On examination, you note hyperaemia and a white deposit on the cornea. what is it
Bacterial keratitis
which common conditions lead to Charles Bonnet syndrome
age related macular degeneration, followed by glaucoma and cataract.
sx of Charles Bonnet syndrome
well formed, vivid, elaborate, and often stereotyped visual hallucinations in a partially sighted person who has insight into the unreality of what he or she is seeing.
A 6m child with 5m history of a rapidly growing bright red lesion on his right upper eyelid.
right upper eyelid bisects the pupil and the lesion blanches on pressure
mnx?
large haemangioma that is obstructing vision
so BB first line
which medication can raise IOP
topical steroids, steroid eye drops, and systemic steroids