week 2 ocular trauma Flashcards
mechanism of injury for ocular trauma?
Blunt trauma
Penetrating trauma;
large objects
small objects
Burns:
chemical
physical
how do you assess ocular trauma?
good Hx
visual acuities
exam of eye: lids, conjunctiva, cornea, anterior segment, pupils, fundus (use fluorescein drops)
what do fluorescein drops do?
identify area of epithelial loss
what accounts as negligence for not doing?
Visual acuities
what are the 6 golden rules of eye trauma?
- History is key
- Always record visual acuity
- Don’t forget Fluorescein
- Handle suspected globe rupture with care…
- X-Ray orbits if suspicion of Intra-Ocular Foreign Body (IOFB)
- Immediate irrigation of chemical injuries
(the solution to pollution is dilution!)
what does the teardrop sign indicate on CT/MRI?
orbital blowout #
what can prolapse due to an orbital blowout #?
orbital fat +/- IR
means they can’t look up
what to do in the case of subconjunctival haemorrage
usually self-limiting. leave to settle like any other bruise
what to do in idiopathic subconjunctival haemorrhage
check BP (high BP is a cause)
what do do in large and boggy subconjuncitval haemorrhage?
suspect globe rupture, investigate under anaesthetic (fix if necessary by surgery)
HANDLE SUSPECTED GLOBE RUPTURE WITH CARE… (AS MAY PROPLASE OUTWARDS VITURAL/RETINA)
WHY DOES TRAUMATIC UVEITIS occur?
iris muscle becomes inflamed and breaks down the blood aqueous barrier, proteins then lookout of damaged vessels into ant.chaber and inflammation occurs giving red eye and uveitis
what is a Hyphaema?
blood in ant.chamber
what to do with a hyphaema?
caused by serious injury - investigate further
in severe trauma tearing of theintra-ocular structures can occur. what structures are normally torn?
limbus.
zonules (causes a dislocated lens)
retinal detachment 2 types what are they?
very short sighted people
trauma
what occurs in a retinal detachment
fluid gets under retina and it peels away
what causes optic nerve avulation?
rare,
trying to remove someones eye forcefully
choroidal tear key facts
rare, can’t really treat it.
what is Commotio Retinae? treatment?
“Bruised retina” - due to severe trauma
settles over time but if involves macula may never fully recover vision (central and severe)
how can you investigate Severe intra-ocular disruption
US probe - if have no idea what’s going on
what to do in large penetrating object in the eye?
multi-displinary team approach
one case of a lid laceration
dog attack on kid
corneal laceration how to investigate?
fluorescene in eye, will see leaking injury= siedels test
what is seidels test used for?
used to assess the presence of anterior chamber leakage in the cornea. It is used as a screening test for many corneal disorders including corneal post-trauma, corneal perforation and corneal degeneration. (corneal LACERATION)
what is a teardrop pupil shape as sign of? why does it occur?
corneal laceration.
iris can plug up the gap
what to do with scleral laceration?
repair under anaesthetic, surgical closure
what to do in fish hook injury?
occurs in fly fishers
surgery; do not pull hook out
what causes Sympathetic ophthalmia
Penetrating injury to one eye
exposure of intra-ocular antigens auto-immune reaction in both eyes.
where do small particles/foreign bodies commonly affect the eye?
painful but okay = Sub-tarsal
Conjunctival
Corneal
potentially serious + visually debilitating = Intra-ocular
Intra-orbital
what is an ICE RINK CORNEA as sign of?
metal foreign body every time you blink scraping the cornea
how to treat a corneal abrasion/FB
anaesthetic, remove FB, chloramphenicol drops (4x daily for 1 week)
when should you be more suspicious of a Penetrating foreign body
Pupil irregular
Anterior Chamber shallow (low IOP)
Localised cataract (trauamtic and acute)
Gross inflammation.
Intra-ocular foreign body (IOFB) how to investigate? commonly caused by?
Always X-ray potential IOFBs (good history)
Fast moving particles
eg hammer and chisel injuries (glasses not 100% effective)
what two types of chemical burns to the eye are there? which is worse?
acid and alkali. alkali worse because acid coagulates proteins, does little penetration and is self limiting
why are alkali chemical burnt to the eye worse?
- cicatrising changes to conjunctiva and cornea
- penetrates the intra-ocular structures
- easy, rapid penetration
what is a bad prognostic sign in an alkali burn?
Alkali burns look less severe than acid but cause ischaemia.
ischaemia around the limbus very bad (as that is where the corneal stem cells are - means scarring is worse)
after a chemical burn what causes problems with vision?
scarring affects vision
Corneal vascularisation is a sign of chronic scarring
end stage scarring is where lids close over and conjunctiva covers cornea
how to manage chemical injury?
Assessment of chemical injury occurs after thorough irrigation.
quick Hx (chemical, when, irrigation at event?)
check Toxbase
check pH
IMMEDIATE irrigation = 2l of saline or until pH is normal
THEN…assess with silt lamp
what to do if Lime / Cement dust in eye?
remove physically as using water creates alkaline solution
