ophthalmology infections/trauma Flashcards
what is dacrocystitis
inflammation of the lacrimal sac // infection of stagnant tears
how does dacrocystitis usually present
a painful lump at the side of nose adjacent to the lower lid
what is the treatment of dacrocystitis
BSABs
where in the eye is redness most obvious in anterior blepharitis
lid margin more red than deeper part of lid
does anterior or posterior blepharitis involve the eye lashes/lash follicle?
anterior
what are the 2 types of anterior blepharitis
seborrhoeic (squamous) and staphylococcal (infection involving the lash follicle)
what are some symptoms of seborrhoeic (squamous) blepharitis
scales on lashes
gritty eye/foreign body sensation
mild discharge
no ulceration
what are some symptoms of staphylococcal blepharitis
lashes distorted teepee sign loss of lashes ingrowing of lashes (trichiasis) styes ulcers of lid margin corneal staining
what is the teepee sign
lashes stuck together
what is a stye
acute purulent infection of a lash follicle
what causes the ulceration in staphylococcal anterior blepharitis
exotoxin
what is another name for posterior blepharitis
meibomian gland disease
what dermatology condition is associated with meibominan gland disease
acne rosacea
what are meibomian glands
specialised glands of eyelid which secrete an oily substance that prevents evaporation of tear film
what are chalazia
meibomian cysts
where is the eye most red in posterior blepharitis
redness is in deeper part of lid - lid margins often look normal
what is seen at the meibomian gland openings in MGD
pouting, swollen, dried secretion
what is the treatment for MGD
lid hygiene (daily bathing/warm compress) supplementary tear drops fusidic acid oral doxycycline for 2-3 months steroid drops
is MGD easy or difficult to treat
difficult to eradicate
what is sjogrens syndrome triad
keratoconjunctivitis sicca (dry eyes)
xerostomia
rheumatoid arthritis
what is the most common form of conjunctivitis
bacterial
what are the most common causes of bacterial conjunctivitis in older ages
staph aureus
strep pneumonia
H. influenza
what are the most common causes of bacterial conjunctivitis in neonates
staph aureus
neiserria gonorrhoea
chlamydia trachomatis
what are some symptoms of bacterial conjunctivitis
almost always bilateral sore or gritty eye good vision red and sticky eye purulent thick yellow discharge/pus presence of papillae (tiny bumps like bubble wrap with little red dot in centre - blood vessel)
what is the treatment of bacterial conjunctivitis
topical chloramphenicol
fusidic acid
gentamicin
when should chloramphenicol be avoided
if history of allergy or asplastic anaemia
what can be given if someone is allergic to chloramphenicol
fucithalmic
what is the treatment for gonoccal conjunctivitis
oral and topical penicillin
what should you suspect in a young adult with bilateral conjunctivitis
chlamydial conjunctivitis
describe the course of disease with chlamydial conjunctivitis
slow/chronic onset of symptoms
mild discomfort for weeks and unresponsive to treatment
what are some symptoms of chlamydial conjunctivitis
watery discharge
symblepharon
assoc. hair follices + little wet rice grains (bumps in lower inside of eyelid)
what is symblepharon
palpebral conjunctiva gets stuck to bulbar conjunctiva causing turning in of eyelid
what is the treatment for chlamydial conjunctivitis
topical oxytetracycline topical erythromycin (also in neonates)
what organism causes trachoma
chlamydia trachomatis
where is trachoma seen and what does it cause
tropics and middle east
blindness
what may precede viral conjunctivitis
cold or flu
is viral conjunctivitis contagious?
yes very
what is the discharge like in viral conjunctivitis
watery
what are the 3 main causative viruses of viral conjunctivitis
adenovirus
HSV
HZV
what are some symptoms of viral conjunctivitis
chemosis
lid oedema
palpable pre-auricular lymph nodes
assoc. follicles (little wet rice grains - bumps in lower inside of eyelid) - bigger bump with red around periphery
is HSV conjunctivitis usually unilateral or bilateral
unilateral
what cutaneous feature is seen in HSV conjunctivitis
cutaneous vesicles on eyelids and around skin of eye
what kind of ulcer is seen in HSV conjunctivitis
dendritic corneal ulcer
where does HSV sit and reactivate from
CN V ganglion
what is Hutchinson sign
tip of nose - means involvement of nasociliary branch of trigeminal nerve
what is the treatment of viral conjunctivitis
self limiting
lubricants and cold compress
strict hygiene
topical steroids when corneal involvement
HSV - aciclovir
how does molluscum contagiosum involve the eye
pearly umbillicated nodules filled with DNA pox virus can be seen on lid margin
and red eye that generally goes unrecognised
what are some treatments for molluscum contagiosum conjunctivitis
curetting in central portion of lesion
freezing the centre
completely excising lesion
short course of topical steroids (prednisolone or dexamethasone) if eye is very involved
what is the main feature of allergic conjunctivitis
itch
what are some features of allergic conjunctivitis
itch redness soreness watery, stringy discharge can cause chemosis
what is the treatment for allergi conjunctivitis
reduce allergen
antihistamines (e.g. azelastine, emedastine)
topical mast cell stabiliser (e.g. sodium chromoglicate, nedocromial)
Olopatadine - dual action, very effective
how could unilateral orbital trauma cause diplopia
if it is associated with the zygomatic bone
what may be needed in order to examine an eye with a corneal abrasion
topical anaesthetic drops
give 2 examples of topical anaesthetic drug
oxybuprocaine or tetracaine
what s/s might indicate a corneal abrasion
severe pain lacrimation inability to open eye (blepharospasm) might be aggravated by blinking/moving eye foreign body sensation reduced visual acuity
what 3 investigations would be done for a suspected corneal abrasion
blue light + fluorescein
eversion of upper eyelid
if suspect IOFB - XRAY
what does a tear drop pupil indicate
corneal penetration
test to prove corneal penetration
Seidel’s test (fluorescein)
what can be a complication of corneal penetration
retinal damage
what is worse an acid or alkali burn and why
alkali burn
acid coagulates causing little penetration
what is the treatment for a chemical injury of the eye
immediate irrigation with minimum 2L saline or until pH normal
what is sympathetic ophthalmia
penetrating injury to one eye causes inflammation of both eyes - exposure of intraocular antigens –> autoimmune reaction in both eyes
how can a corneal ulcer lead to permanent visual loss
healing occurs by collagen laying down in a haphazard fashion
give 4 causes of a central corneal ulcer
viral (HSV - dendritic ulcer)
fungal
bacterial
acanthamoeba
what is the treatment of a dendritic ulcer
aciclovir
what is the treatment of a bacterial corneal ulcer
ofloxacin hourly
what are some cause of a peripheral corneal ulcer
RA
GPA, polyarteriitis (rarely)
hypersensitivity - marginal ulcers
what is the treatment of a peripheral corneal ulcer
oral/topical steroids
what are the 3 layers of the cornea
epithelium (10%)
stroma (90%)
endothelium
when should keratitis be suspected
if cornea stains with fluorescein
what are some s/s of keratitis
foreign body sensation pain photophobia lacrimation vision reduced (if ulcer which affects visual axis)
how does a dendritic ulcer form
HSV keratitis - epithelial cells undergo lysis and form a dendritic ulcer
how is a dendritic ulcer observed
blue light and fluorescein
true or false
HSV keratitis is not very painful and is recurrent
HSV keratitis is very painful
can be recurrent
where does HSV lie dormant
CN V ganglion
what is the treatment of HSV keratitis
aciclovir
what happens if steroids are used in HSV keratitis
can lead to spread of virus + ulcer increases in size and corneal melt and perforation
DO NOT USE
what usually precedes adenoviral keratitis
URTI
is adenoviral keratitis usually unilateral or bilateral
bilateral
what may be seen in adenovrial keratitis
subepithelial infiltrates
what is the treatment of adenoviral keratitis
topical chloramphenicol - prevent secondary infection
steroids if chronic
what is usually seen with bacterial keratitis
hypopyon
what is the treatment for bacterial keratitis
hospital admission for hourly administration of drops - ofloxacin
what is bacterial keratitis usually assoc. with
other corneal pathology or contact lenses
when does acanthamoeba (fungal) cause keratitis
contact lens wearers
farmers
what is the treatment for acanthamoeba keratitis
chlorhexidene (every 30 mins for 6 days)
what is another cause of keratitis in contact lens wearers
pseudomonas aeruginosa
what is the treatment for keratitis caused by pseudomonas aeruginosa
gentamicin
