Conditions Flashcards
What is acute angle closure glaucoma
when your iris and cornea move closer together, increasing the intraocular pressure because there is no way to drain the fluid
this causes damage to the optic nerve (glaucoma)
What causes acute angle closure glaucoma
when the gap between your iris and your cornea closes because e.g.
you:
- go into a dark room
- get dilating eye drops
- are excited or stressed
- take drugs e.g. antidepressants
- have cataracts, diabetic retinopathy or tumours
What health conditions are risk factors for acute angle closure glaucoma
cataracts
ectopis lens (lens moves from where it should be)
diabetic retinopathy
ocular ischaemia
Uveitis
Tumour
what is the epidemiology of acute angle closure glaucoma
- Women
- SE Asian
- Farsighted
- 55-65
what are the symptoms of acute angle closure glaucoma
- eye pain
- severe headache
- nausea/ vomiting
- blurry vision
- redness in eye
What tests do you do to diagnose acute angle closure glaucoma
Gonioscopy (microscope with slit lamp- checks angle between iris and cornea and sees how well fluid drains)
Tonometry (measures intraocular pressure)
Opthalmoscopy (for damage to optic nerve)
How do you treat acute angle closure glaucoma
Initially:
- eye drops containing beta-blockers to reduce fluid production e.g. Timolol
- IV acetazolamide (to reduce IOP)
Then Bilateral peripheral iridotomy
Pilocarpine eye drops which constrict pupil (aren’t used much anymore)
What is Orbital Cellulitis
infection of soft tissues of the eye socket posterior or deep to the orbital septum (divides eye lid from eye socket
What is the difference between orbital and peri-orbital cellulitis and which one is more severe
Orbital is inflammation of the soft tissue posterior/ deep to the orbital septum
Peri-orbital is anterior to the septum (superficial upper eyelid)
orbital is more severe because it actually affects stuff in the orbital cavity
What is the cause of orbital cellulitis
when an exisitng infection spreads from its origin
most commonly when a bacterial infection spreads from the paranasal sinuses e.g. ethmoid
or eyelid skin infection spreads
Which bacteria most commonly cause orbital cellulitis
Staph. aureus
Streptococci e.g. group A B haemoltyic, pneumoniae,
How do you investigate someone with orbital cellulitis
CT scan
Full blood count (leukocytosis (high))
blood culture prior to administration of antibiotics
how does orbital cellulitis present (history and examination)
History:
fever, malaise, recent sinusitis/ URT infection
often recent facial trauma/ surgery/ dental work
- decreased vision
- eye pain
- swelling
- erythema
- edema of eyelids
- proptosis (bulging)
OE:
- elevated IOP
- RAPD
How do you treat orbital cellulitis
prompt hospitalisation
broad spectrum IV antibiotics for 1-2 weeks e.g. Ceftriaxone, ampicillin-sulbactam, moxifloxacin
surgery:
- canthotomy and cantholysis (incision into canthi) if orbital compartment syndrome is diagnosed (very high IOP)
- drain if abcess
ENT consultation if recent sinusitis
give 3 examples of antibiotics for orbital cellulitis
Ceftriaxone, ampicillin-sulbactam, moxifloxacin
what is the difference between penetrating and perforating eye injuries
penetrating= penetrated into eye but no exit wound
perforating= entrance and exit wound
both aka open globe injury
what are the risk factors for a penetrating/ perforating eye injury
male gender
occupation
how does a penetrating/ perforating eye injury present
- pain
- double vision
- foreign body sensation
- blurred vision
- redness
- light sensitivity
how do you investigate an open globe injury
aka penetrating/ perforating eye injury
visual acuity and pupillary exam important
gentle ultrasound and computed tomography
how do you manage a penetrating/ perforating eye injury
prophylactic antibiotics e.g. vancomycin, cephalosporin
surgery to close the open globe
what are the two types of chemical injury to the eye and which is worse
acid or alkali
alkali is much worse because the acids denature and cant pass the phospholipid bilayer where as alkali burrows down
what are the common causes of chemical eye injuries
acid:
- HCL (cleans swim pools)
- Sulphuric acid (car batteries)
Alkali:
- sodium hydroxide (drain cleaner)
- ammonia (bleach)
- calcium hydroxide
how do you treat a chemical eye injury
irrigation with any noncaustic fluid available until pH of ocular surface is between 7 and 7.2
depending on severity treat with antibiotics, control inflammation, debridement
what are the common causes of conjunctivitis
Viral:
- HSV
- VZV
Bacterial:
- Staph. aureus
- haemophilus influenzae
- strep. pneumoniae
- pseudomonas
Allergens:
- pollen
- moulds
Think STIs
How does conjunctivitis present
- red sclera
- increased tearing
- thick yellow discharge that crusts over the eyelashes (bacterial)
- itchy eyes (allergic)
- blurred vision
- photosensitive
- swollen eyelids
how do you investigate conjunctivitis
slit lamp
visual acuity tests
eye culture if stays for 2-3 weeks
how do you treat conjunctivitis
bacterial= antibiotics e.g. levofloxacin
viral= let it run its course- help with cold compress
allergic= antihistamines (drops)
what are the typical causes of corneal ulcers
Bacterial=
- stap. aureus
- strep. pnuemoniae
- pseudomonas
Viral=
- HSV
- VZV
what are the risk factors for corneal ulcers
contact lenses (especially overnight ones)
steroid eye drops
existing eye conditions e.g. blepharitis, dry eyes
how do corneal ulcers present
- pain
- redness
- foreign object sensation
- tearing
- photophobia
- decreased vision
how do you investigate corneal ulcers
slit lamp with fluorescein stain to diagnose
cornea culture to rule out infectious cause
how do you treat corneal ulcers
- artificial tears
- systemic immunosuppressive therapy (methylprednisolone)
- corneal transplant if severe
What causes giant cell arteritis
actual cause is uncertain
associated with autoimmune disease
it is an autoimmune disorder
how does giant cell arteritis present
bilateral temple pain and scalp tenderness
jaw pain
vision loss/ diplopia
fever
fatigue
weight loss
how do you investigate giant cell arteritis
increased ESR, CRP, thrombocytosis
temporal artery biopsy to diagnose
how do you treat giant cell arteritis
immediate high dose corticosteroid (e.g. prednisone)
what are the 3 causes of retinal detachment
Rhegmatogenous (most common):
- hole/ tear in the retina so fluid can pass under it pulling it away from underlying tissue
- most commonly caused by ageing which causes posterior vitreous detachment
Tractional:
- scar tissue on surface
- in poorly controlled diabetes
Exudative:
- fluid accumulation under the retina
- caused by age-related macular degeneration, tumour
what are the risk factors for retinal detachment
age (posterior vitreous detachment)
Previous retinal detachment
family history
extreme myopia
Poorly controlled diabetes (tractional)
age-related macular degeneration (exudative)
eye injury (exudative)
inflammatory disorders (exudative)
Symptoms of retinal detachment
painles
sudden appearance of floaters
flashes of light
blurred vision
gradually reduced peripheral vision
curtain going down/ up
investigations of retinal detachment
to diagnose:
Visual acuity testing
slit-lamp examination,
opthalmology
treatment of retinal detachment
surgery to repair detachment
photocoagulation (welding) or cryopexy (freezing) to weld the retina to the eye wall if tear hasnt progressed to detachment
what is amaurosis fugax
transient loss of vision in one or both of the eyes
cause of amaurosis fugax
plaque/ blood clot in the carotid artery (at the side of the lesion)
what are the risk factors for amaurosis fugax
heart disease
hypertension
high cholesterol
smoking
alcohol
cocaine
MS
optic neuritis
how does amaurosis fugax present
vision loss in one or both eyes
grey curtain that progresses from the periphery towards the centre
no pain, lasts 2-30 mins
how do you investigate amaurosis fugax
blood pressure (hypotension could be cause)
FBC for anaemia
ESR and CRP for elderly patients to rule out GCA
Imaging of carotid arteries to find blockage
how do you treat amaurosis fugax
treat underlying condition
e.g. anticoagulant, hypotensives
lifestyle changes e.g. stop smoking
What is a meibomian cyst
aka chalazion
sterile, inflammatory granuloma caused by obstruction of a sebaceous gland
these run along the eyelid margin and produce secretion which provides lipid layer of tear film
cause of meibomian cyst
obstruction of a sebaceous gland
these produce a lipid secretion which makes the lipid layer of tear film
what are the risk factors for a meibomian cyst
Chronic blepharitis
Rosacea (red face)
how does a meibomian cyst present
painless bump in eyelid (usually upper)
mild irritation causing watery eyes
blurred vision if it is large and pushes on the eyeball
how do you treat a meibomian cyst
application of warm compress for 10-15 mins
gentle massage 5 times a day
what are the common causative organisms of blepharitis
low grade infections
staph. epidermidis
staph. aureus
what causes blepharitis
unclear
can spread from person to person
can be associated with other conditions e.g. seborrheic dermatitis, infection, rosacea
what are risk factors for blepharitis
seborrheic dermatitis
rosacea
diabetes
allergies
symptoms of blepharitis
watery eyes
red eyes
stinging eyes
greasy eyelides
red eyelids
swollen eyelids
flaky skin
photosensitive
blurred vision- improves with blinking
how do you investigate blepharitis
if severe:
lid biopsy
lid margin culture
but usually none
how do you manage blepharitis
self-care e.g. washing, warm compreßes
if doesnt work then antibiotics/ steroid drops
what causes corneal abrasions
when your cornea gets scratched by contact with dust, dirt, sand, wood shavings etc
how does corneal abrasion present
eye pain
tearing
photosensitivity
foreign body sensation
blurry vision
blepharospasm
how do you treat a corneal abrasion
flush with clean water/ saline
lubricating eye drops to keep moist
antibiotics if severe
how does a corneal foreign body present
eye pain
foreign body sensation
photophobia
tearing
red eye
decreased visual acuity (blurred vision)
how do you treat a corneal foreign body
antibiotic drops prophylactically e.g. Polytrim
remove foreign body under topical anaesthetia
perhaps topical NSAID for analgesia and anti-inflammatory
what causes uveitis
often unknown cause
associated with auto-immune diseases e.g. UC, sarcoid, idiopathic juvenile arthritis
can be infective e.g. Herpes, syphillis
how does uveitis present
acutely with red eye
pain
blurred vision
photosensitivity
floaters
chronically with floaters and blurred vision
how is uveitis treated
if infective antimicrobial
if auto-immune with steroid eye drops
cause of episcleritis and scleritis
often no apparent cause
often underlying stystemic inflammatory condition e.g. rheumatoid arthirtis, lupus, crohn’s
how does episcleritis present vs scleritis
both have:
- red eye
Episcleritis:
- acute onset
- mild pain
Scleritis:
- subacute onset
- severe pain
- pain on movement
- photophobia
how do you treat episcleritis vs scleritis
episcleritis:
- usually clears without treatment
- often cool compress/ iced arificial tears
scleritis:
- opthalmology consult
- systemic steroids/ NSAIDS
causes of vitreous haemorrhage
conditions which cause the formation of new, abnormal blood vessels:
diabetic eye disease
macular degenration
retinal vein occlusion
retinal tear causing posterior vitreous detachment
how does vitreous haemorrhage present
visual haze
painless vision loss
floaters
cloudy vision
photophobia
how do you treat a vitreous haemorrhage
laser photocoagulation to stop abnormal vessels from bleeding
other treatments e.g. cryotherapy can be used
treat underlying condition e.g. diabetes
what causes dry eyes
- dysfunction in any of the three tear layers (fatty, mucus, water)
reasons e.g. hormone changes, autoimmune disease, inflamed eyelid glands - decreased tear production (keratoconjunctivitis sicca) due to aging, Sjogren’s syndrome, RA, meds (e.g. antihistamines, antidepressants), corneal nerve desensitivity through contact lens use
- increased tear evaporation due to posterior blepharitis, allergies
what are the risk factors for dry eyes
age (over 50)
women (oestrogen/ pill)
Vit A deficiency
Contact lenses
how are dry eyes treated
education/ modify environment (e.g. humidifier)
topical ocular lubricants (artifical tear drops)
topical anti-inflammatory eye drops
how do dry eyes present
stinging, burning, itchy
stringy mucus in/ around eyes
photophobia
eye redness
foreign body sensation
what causes a blocked naso-lacrimal duct
congenital
age- related (puncta get narrower)
infection/ inflammation e.g. sinusitis
tumour
chronic eyedrop use
what are the risk factors for a blocked naso-lacrimal duct
age
chronic eye inflammation
previous surgery
glaucoma (higher pressure)
previous cancer/ treatment
how does a blocked naso-lacrimal duct present
excessive tearing
scleritis/ conjunctivitis
painful swelling near puncta
crusting of the eyelids
blurred vision
how do you treat a blocked naso-lacrimal duct
depends on cause
if infective cause treat infection
e.g. congenital often gets better by itself
dilation with stent/ balloon
what causes cataracts
clouding of the lense caused by proteins and fibres in the lenses breaking down and clumping together
usually caused by age/ injury
what are risk factors for catraracts forming
age
diabetes
excessive sunlight exposure
smoking
obesity
hypertension
how do cataracts present
clouded, blurred vision
photophobia
halos around lights
diplopia in one eye
how do you treat cataracts
surgery to remove lens and replace with a new one
what causes of open angle glaucoma
blockage of the trabecular meshwork
what are the risk factors for open angle glaucoma
- high IOP
- age
- black, asian, hispanic
- family history of glaucoma
how does an open angle glaucoma
insidious- asymptomatic in the early stages
patchy blind spots in peripheral/ central vision frequently (bilateral)
often will be found after visual acuity test
how do you investigate open angle glaucoma
tonometry
slit lamp- mycrocystic oedema
gonioscopy through slit lamp to check angle
how do you treat an open angle glaucoma
eye drops to lower IOP:
- latanoprost, bimatoprost to improve drainage
- timolol, dorzolamide to reduce eye fluid formation
trabeculectomy to create a channel in the iris for flow of aqueous humour
laser treatment targeting trabecular meshwork
what are the causes of macular degeneration
unknown cause
macular tissue thins and loses cells
what are the risk factors for macular degeneration
age!!!! family history race (caucasian) smoking obesity CV disease
how does macular degeneration present
visual distortion e.g. straight lines seeming bent
reduced central vision (mono or bilateral)
difficulty in low light levels
how do you investigate macular degeneration
Amsler grid
tomography
angiography to determine if blood vessels are getting adequate blood flow and to investigate the extent of degeneration
how do you treat macular degeneration
Dry- no treatment but vision aids can help symptoms
Wet:
- Bevacizumab, ranibizumab to stop new blood vessel growth (injections)
- photodynamic therapy if abnormal blood vessels at fovea (light activates verteporfin injected in arm vein)
- photocoagulation to seal abnormal blood vessels (can cause blind spot)
what is a 3rd nerve palsy
damage to oculomotor nerve/ branch thereof
affects 4/6 extrocular muscles (lateral rectus and superior oblique spared)
what is the cause of 3rd nerve palsy
either congenital or acquired
acquired can be microvascular, trauma, compression from neoplasm or post-neurosurgery
how does 3rd nerve palsy present
- complete ptosis (closed eyelid)
- deviation of the eye out and down
- enlarged pupil and doesnt react to light
what is the most life-threatening type of nerve palsy
third nerve palsy
because a subset of them are caused by life-threatening aneurysms
how do you treat third nerve palsy
surgery if tumour or aneurysm
vision therapy
eye patch patching
usually recovers in 3 months
what causes 4th nerve palsy
congenital
trauma
microvascular disease
how does 4th nerve palsy present
diplopia
hypertropia (one eye deviates up)
further elevation as it moves medially
is 4th nerve palsy dangerous
could be a symptom of a stroke
6 months for spontaenous resolution
eye muscle surgery recommended which speeds it up
what causes 6th nerve palsy
stroke
brain aneurysm
diabetic neuropathy
trauma
infection
how does 6th nerve palsy present
dipolpia
strabismus (eye might be slightly adducted cos no lateral rectus function)
how do you treat 6th nerve palsy
will sometimes disappear without treatment
steroids if inlfammation suspected
eye patch
