Ocular Trauma Flashcards
1
Q
What are the 2 classifications of ocular trauma and what are their sub-types?
A
- Non-mechanical:
o Chemical
o Thermal
o Electrical
o Radiation - Mechanical:
o Contusion
o Perforation
2
Q
Give examples of types of trauma?
A
- Eyewall: sclera & cornea
- Closed globe injury: no full thickness wound of eyeball, e.g. ‘black eye’
- Open globe injury: full thickness wound of eyeball, contents of eye poking out
- Contusion: there is no (full thickness) wound
- Lamellar laceration: partial thickness wound of eyewall
- Rupture: full thickness wound of eyewall, caused by a blunt object
- Laceration: full thickness wound of eyewall, caused by a sharp object e.g. knife or shard of glass
- Penetrating injury:
o Entrance wound
o Retained foreign object(s) - Perforating injury: entrance & exit wounds
3
Q
Which clinical assessments need performed in ocular trauma?
A
- Incident – what happened?
- Symptoms
- Px’s Ocular History (OH)
- Px’s medical history
- Family Ocular History (FOH)
- Drugs, allergies
- Visual function
- Orbit intact
- Motility
- Conj, cornea, anterior chamber
- Gonioscopy, iris, lens, vitreous
- Tonometry (IOPs), VFs, indirect ophthalmoscopy
- Photos – if possible
4
Q
Describe the chemical injuries?
A
- Most destructive of all traumatic events to eye
- May occur at home or work
- Severity depends on type of chemical:
o Liquid
o Vapour
o Gas
o Solid - Extent of damage depends on time of exposure
- Types:
1. Alkalis – cleaning substances, soapy feel
2. Acids – car batteries (sulphuric acid)
3. Organic solvents used in paints, glues
4. Surfactants (wetting agents): in soaps & detergent
5. Aerosols: powders, or droplets, suspended in a gas - 2/3 occur at home
- Usually accidental
- Severity from trivial to blinding
- Clinical features:
o Conj injection or blanching
o Chemosis
o Haemorrhage
o Epithelial defects
o Corneal oedema – painful
o Perilimbal ischaemia – blanched limbal vessels with no visible blood flow
o Anterior chamber activity – flare or cells for e.g. retinal cells
o ↑ IOP
5
Q
Describe Alkali burn injuries?
A
- Most severe
- Twice as common as acid burns
- Alkali commonly used in household cleaning agents
- Alkalis tend to penetrate tissue deeper than acids
- Sever conj reaction & stromal opacification blurring iris
- Grading (after Hughes):
o Grade I - Clear cornea, no limbal ischemia (good prognosis)
o Grade II - Hazy cornea, visible iris, < 1/3 limbal ischemia (good prognosis)
o Grade III - Opaque cornea, stromal haze, iris details obscured, 1/3 - 1/2 limbal ischemia (guarded prognosis)
o Grade IV - Opaque cornea, iris details obscured, > 50% limbal ischemia (poor prognosis)
6
Q
Describe Acid Burn injuries?
A
- Potentially less severe than alkalis
- Do not affect deeper tissue layers
- Clinical features are generally similar to alkali injuries
- Clinical features:
o Generalised redness
o Lid oedema (swelling)
o Small conj haemorrhages
o Conjunctivitis - Prolonged exposure may cause:
o Ulceration & opaqueness of corneal & conjunctival epithelium
o Permanent haze & vascularisation
7
Q
Describe organic solvent injuries?
A
- Do not usually cause permanent damage
- May cause:
o Irritation
o Punctate keratitis (epithelial)
o Stromal damage
o Lacrimation
o Pain
o Photophobia
o Stinging
8
Q
What is the emergency management for chemical injury?
A
- Only eye injury that requires IMMEDIATE tx & careful examination
- IRRIGATE, IRRIGATE, IRRIGATE
- Neutralise pH – before taking hx
- Copious irrigation to minimise contact time of chemical
- Regular saline for 15-30min
- If not available: cold tap water
- Evert lids
- Remove any particles from lids/fornices
- Topical anaesthetic for comfort
9
Q
Describe the medical treatment for chemical injuries?
A
- Topical antibiotics as prophylaxis
- Topical steroids to reduce inflammation – but these impair stromal healing
- Topical cycloplegia
- Topical lubricants
- Oral analgesia
- All topical tx preservative free if possible
- If IOP elevated: tx indicated
- Ascorbic acid (topical & systemic) – improves wound healing
- Topical citric acid (sodium citrate) – inhibits neutrophil activity, reduces inflammation
- Surgery e.g. penetrating keratoplasty for opaque corneas
10
Q
What are 2 examples of mechanical injury?
A
Fireworks
Blunt trauma
11
Q
Describe blunt trauma?
A
- Often caused by flying blunt objects
- Rugby/ football injury - elbow
- Ocular damage may be result of wave forces travelling through liquid contents of eye
o This may cause an explosive force within globe - Commonly associated with more complex injuries
12
Q
What are the clinicl features of blunt trauma?
A
- Anterior segment:
o Corneal abrasion
o Corneal oedema
o Hyphema – more serious as don’t know where blood is leaking from
o Miosis
o Mydriasis
o Cataract - Posterior segment:
o Posterior vitreous detachment
o Retinal oedema
o Retinal breaks
o Macular holes
o Choroidal rupture
o Traumatic optic neuropathy
13
Q
What is the management for blunt trauma?
A
- Primary repair of globe
- Secondary: surgical repair of iris, lens or other affected structures
- Frequently hospital-based, usually under general anaesthesia
14
Q
What is traumatic optic neuropathy?
A
- Caused by transmission of force through the orbital bones due to a trauma to the orbit, forehead, or brow:
o shearing of optic nerve fibres
o haemorrhage
o optic nerve oedema
o vision loss - Referral of any patient with suspected traumatic optic neuropathy
- Clinical Sign: optic disc haemorrhage
15
Q
Describe fractures to the orbit?
A
- Caused by blunt trauma
- Involved broken orbital bones
- Symptoms include:
o swelling of the eyelid
o bruising around the eye
o eye pain
o double vision
o reduced motility of the affected eye - Specific type: Blow-out fracture:
o Orbital floor or medial wall affected
o Muscle may get trapped in fracture
o Motility problems, esp. when looking up
o Diplopia possible
o Painful
o Patient may have nosebleed
16
Q
Describe ocular trauma to the anterior segment?
A
- Cornea:
o Superficial foreign body (common) - Conjunctiva:
o Subconjunctival haemorrhages can occur, not sight-threatening, referral not essential - Anterior chamber:
o Hyphaema is potentially more serious – May cause secondary glaucoma - Iris:
o Iris damage may give rise to traumatic mydriasis or traumatic miosis (temporary or permanent)
o Patients may experience glare
o Angle recession and glaucoma may develop - Lens
o Dislocation possible
17
Q
Give examples of ocular foreign bodies?
A
- Dust, sand, or paint that gets into the eye
- Superficial FB: sticks to the front of the eye
- May get trapped under one of the eyelids
- Possible causes:
o Grinding
o Working under a car
o Being outside on a windy day - Superficial FB not usually serious
18
Q
What are clinical features of superficial FB?
A
- May cause corneal abrasion
- Symptoms:
o Ocular irritation, pain, photophobia, tearing - Signs:
o Conjunctival injection - Diagnosis:
o Slit lamp
o Corneal staining with fluorescein - Treatment:
o Remove FB (e.g. cotton bud)
o Topical anaesthetic if required (comfort)
o Artificial tears, topical cycloplegic, antibiotic eye drops/ ointment - Aim: rapid epithelial healing
- Prognosis: usually good, not serious to sight
19
Q
Give examples of mechanical injuries to ocular structures?
A
- Horse riding: Falling off &/or Horse kicking:
o Dislocated crystalline lens:
Cause: broken zonular fibres
May result in monocular diplopia
Associated with iris tremor due to lack of support of iris from lens
Cataract may occur
o Hyphaema:
Blunt trauma causing blood to anterior chamber - Penetrating FB e.g. fish hook:
o OCULAR EMERGENCY
o Penetrate the outer layer of the eye (cornea or sclera) and enter the eye
o Tiny objects usually travelling at high speed
o Risk of vision loss - Lid contusion:
o ‘Black eye’: indicates damage of orbit and lids - Subconjunctival haemorrhage
- Lower lid laceration e.g. from shard of glass or knife
20
Q
What can occur when there is posterior segment damage?
A
o retinal oedema
o retinal tears
o retinal detachment
o vascular changes
Sight-threatening, requires urgent medical attention
