Management of ocular trauma Flashcards
what is a corneal abrasion
list 3 causes that it may be due to
Corneal abrasions are superficial defects in the epithelium of the cornea
May be due to:
- Trauma (fingernail, twig, edge of paper, mascara brush)
- Sub-tarsal foreign body (abrasion gets adherent to upper sub-tarsal plate and abrades cornea as px blinks)
- Contact lens trauma (may be trying to remove a lens thats not actually there or aggressive during insertion and removal or from the lens itself)
name a direct and a secondary cause of a corneal abrasion
Direct: trauma
Secondary: Sub-tarsal foreign body
which type of corneal abrasion are common
what do they account for, by how much and why
Traumatic abrasions are common
Accounting for approx. 40% of acute ophthalmic presentations to A and E departments
Because of the acute pain associated either by the abrasion or the foreign body
list 3 predisposing factors of a corneal abrasion
Corneal dystrophy - such as an epithelial basement membrane dystrophy (Cogans)
Diabetes - has more fragile epithelium so breaks down more easily
Neurotrophic keratitis - secondary to hepatic infection caused by herpes simplex virus
explain why/how people with the corneal dystrophy cogans syndrome is a predisposing factor to a corneal abrasion
because normally the cornea is bound down to the stroma by hemidesmosomes and anchoring filaments which holds the epithelium down to the surface of the eye
however is cogans syndrome, this is compromised and there is no good attachments of the epithelium to the underlying stroma = these people are predisposed to corneal abrasions
explain why/how neurotrophic keratitis is a presiposin factor to a corneal abrasion
neurotrophic keratitis is secondary to a hepatic infection by the herpes simplex virus and these people have had a viral keratitis
people with a viral keratitis are found to have a very unhealthy epithelium down to a loss of neural function
the viral keratitis tends to affect the nerve supply to the cornea, the corneal nerves have a alerting mechanism and also has a trophic function (i.e. the epithelium needs a nerve supply in order to maintain it’s integrity)
therefore if we take the nerve sensation away (as with neurotrophic keratitis) = the cornea becomes more vulnerable and the epithelial cells will more readily break down.
list the 4 symptoms of a corneal abrasion
Pain - from any disruption to the surface
Photophobia - just a disturbance from bright light (so not same as uveitis)
Blepharospasm - eyelids forced shut and cannot open from pain
Lacrimation
what is a clinical feature defined as
both signs and symptoms
what are the 7 signs of a corneal abrasion
Lid oedema
Conjunctival hyperaemia (which is mostly associated with pain)
Corneal epithelial defect
Corneal oedema (barrier is removed and water can enter into the cornea from the tear film)
Visual loss (if central abrasion)
May be secondary AC inflammation (when the blood aqueous barrier breaks down)
how can you clinically assess a secondary AC inflammation in someone who has had a corneal abrasion
to look for inflammatory cells and flare from the breakdown of the blood aqueous barrier = protein will be present which gives rise to scatter, called flare
if it is associated with major damage, it will cause a anterior chamber activity
when shining a light from the slit lamp onto the epithelium you will see lots of light scatter and also a lot of light coming back at you from the lens (in the anterior chamber)
list the 5 steps of your clinical assessment of someone who has had a corneal abrasion
Determine cause of injury - from your history to determine how bad the cause is
Measure VA - ALWAYS
Evaluate abrasion with fluorescein
- Size
- Depth - optic section
- Confirm no FB present (evert lid)
Check for AC inflammation - turn off lights completely, as want no background light and use the smallest and brightest beam to detect
Topical anesthesia to aid examination - to help with lid eversion etc
what is the 3 aims of management of a corneal abrasion
Pain control - advise px to buy oral analgesics e.g. ibuprofen
Facilitate healing - at rate which we expect by booking follow up check to see cornea is healing
Infection control - as taken away barrier so prophylactic anti biotic
what 2 things is the choice of topical antibiotic treatment for a corneal abrasion dependent upon
and how will you give the topical antibiotics to this patient if they have either of these
- size and depth of the abrasion
- contamination from organic matter e.g. gardening injuries or debris in the abrasion
you will give the full course of the antibiotic which is either 4x drops per day with ointment at night and continue that for a whole week
if you don’t do it this way then theres no point of doing it at all as theres no benefit of putting chloramphenicol just once at that time
list 8 points about the management and risk of a corneal abrasion
Chloramphenicol 0.5% eyedrops or 1% ointment
For large abrasions 1% cyclopentolate to prevent ciliary spasm (as ciliary spasm is caused by the pain, so it is thought that cyclopentolate will reduce the pain)
Analgesia (topical NASID and/or paracetamol/ibuprofen
No patching as does not improve wound healing
Arrange follow up to monitor healing
Refer if deep abrasion or contaminated with foreign material
Advise on eye protection
Risk of recurrent epithelial erosion syndrome - as when healing, it is still vulnerable to break down recurrently
why is patching not advised as a management option for corneal abrasion and what is better to use instead
because eye padding potentially made the corneal abrasion worse as when the eye is hidden behind the pad = can’t see any changes to that eye, so if it develops any complications following the abrasion, then we would not have known
a thin soft bandage plano CL is a better option to protect the cornea and bridge the pain whilst being able to see any changes occurring to the cornea
give examples of what can cause a sub-tarsal foreign body
FB entering the eye such as:
wind blown
particle falling into the eye (e.g. DIY)
most of the time the tears will wash the FB away, but embedded debris thats stuck on the tarsal plate has to be removed by the clinician
what are the clinical features i.e. 2 signs and 3 symptoms of a sub-tarsal foreign body
Symptoms
- Foreign body sensation (whereby every time the px blinks, will traumatise the ocular surface)
- Lacrimation
Signs
- Hyperaemia
- Embedded FB
- Corneal FB tracks - established by using flourescein
what will be the 4 management steps for a sub-tarsal foreign body
Topical anaesthesia to aid examination
Remove FB by saline irrigation or saline wetted cotton bud - which is easier to do under slit lamp
Consider prophylactic antibiotic if corneal damage
Advise on suitable eye protection
list 3 possible causes of a corneal foreign body
Patient may give a history of foreign body entering the eye
- wind blown
- DIY or gardening
- high velocity (hammering or grinding)
what are the clinical features i.e. 3 signs and 3 symptoms of a corneal foreign body
Symptoms
- Foreign body sensation
- Lacrimation
- Blurred vision - depending on location
Signs
- Embedded FB
- Linear scratches
- Rust ring from ferrous material = contains iron (must be very careful of this as its very toxic to the epithelium)
list the 5 steps carried out in the clinical assessment of a corneal foreign body
Determine cause of injury - by taking a good history
Measure VA
Rule out multiple particles - do a full assessment
Assess depth of corneal foreign body (slit lamp optical section) - slit lamp optic section
Topical anaesthetic may aid examination
what will be your management of a corneal foreign body and what are the 6 steps of doing this
removal of the foreign body
- Loose FB can be irrigated with saline - try this first
- Conjunctival FB removed with cotton bud
- Assess depth of corneal FB with slit lamp
- Embedded corneal FB should be removed with a hypodermic needle
- Check VA before and after removal
- Evaluate need for antibiotic prophylaxis
what should be used to remove a corneal foreign body
a hypodermic needle
describe how a hypodermic needle us used to remove a corneal foreign body
Hold the needle with the bevel uppermost and horizontally ‘flat on’ to the cornea
i.e. bevel should face the optom
Gently lift off the foreign body (FB) from the corneal surface - by doing a rocking motion to scoop the FB off the cornea and flip it out
list 5 points about the further management of a corneal foreign body after it has been removed by the hypodermic needle
Do not patch the eye
Prophylactic antibiotic if risk of infection
Analgesia - for the pain
If penetrate into stroma or presence of rust ring then refer to an ophthalmologist
Advise on suitable eye protection
when should you refer a patient with a corneal foreign body to the ophthalmologist (instead of managing yourself)
if it penetrates into the stroma or in the presence of a rust ring
what 3 things will you think to do if you see a 24 year old student who suffers an injury to his right eye whilst playing squash and what is your diagnosis
History questions
Assessment
Management
Blunt trauma
list 3 possible causes of a blunt trauma
RTA
sport
assault
list the 4 clinical signs of a mild case of blunt trauma
and
list the 6 clinical signs of a severe case of blunt trauma
Mild cases:
- eyelid swelling
- bruising
- sub-conjunctival haemorrhage
- corneal abrasion
Severe cases:
- blow out fracture
- hyphema
- raised IOP
- iridodialysis - iris becoming detached in the periphery at its root
- commotio retinae
- retinal detachment
list the 7 steps carried out in your clinical assessment of a blunt trauma
History (detailed) VA Ocular motility - to check for blow out fractures and diplopia particularly on up gaze IOP Pupils - look for RAPD Anterior eye exam Posterior eye exam
list the 7 signs of a trauma which will cause rd flags and will need referral
Reduced VA Diplopia Enophthalmos Raised IOP Hyphaema Anisocoria/distorted pupil - associated with iris trauma Ruptured/perforated globe - uvea breaking through sclera Vitreous haemorrhage
what change in raised IOP will be a red flag and hence an action to refer the px as a result of trauma
it will be unilateral
so use the other eye as a control
if there is more than 5mmHg difference between the 2 eyes
then it is likely to be a consequence of trauma
list 4 types of ocular trauma from least to most serious
corneal abrasion
sub-tarsal foreign body
corneal foreign body
blunt trauma
