Ocular Trauma Flashcards
Potential causes of ocular trauma?
- Work-related (often minor)
- Assault
- Accidents at home
- Sports-assoc. eye injury
- Other causes
3 mechanisms of injury to the eyes?
Blunt trauma
Penetrating trauma (small or large objects)
Burns (chemical or physical)
Assessment of ocular trauma?
Hx of the incident
ALWAYS ASSESS AND NOTE VISUAL ACUITIES
Examination of the eye (all layers)
During examination of the eye, how can areas of epithelial loss be identified?
Using FLUORESCEIN drops, e.g: for a corneal abrasion, ulcer, scratch, etc
Shining a blue light on to the eye after using eye drops causes it to glow BRIGHT GREEN in areas of epithelial loss
Treatment of a corneal abrasion?
Chloramphenicol QDS for 1 week; if may be given for longer, if necessary
This prevents infections and soothes the eye whilst healing occurs
What is an orbital blowout fracture?
Traumatic fracture to the orbital floor or medial wall, typically resulting from impact of a blunt object, larger than the orbital aperture (e.g: a tennis ball)
Symptoms and signs of an orbital blowout fracture?
Inability to look up (inferior rectus is trapped in the fracture site)
Ix for orbital blowout fractures?
CT scan shows a “tear drop” sign
Cause of deforming injuries to the eye?
Typically caused by globe rupture, which may occur due to:
• Blunt trauma from an object that is smaller than the orbital aperture (e.g: a squash ball)
• Penetrating injury
What is a globe rupture?
Ophthalmologic emergency that can lead to blindness
Integrity of the outer membranes of the eye is disrupted by blunt or penetrating trauma
Signs and symptoms of a globe rupture?
Obvious deformation of the eye
Ix for a globe rupture?
Handle with care
What is traumatic uveitis?
Sub-type of anterior uveitis that is typically caused by blunt trauma
May result with the leakage of proteins and WBCs into the anterior chamber
Signs and symptoms of traumatic uveitis?
Painful red eye that is tearing
Photophobia
Blurred vision
May have a hypopyon
What is a hyphaema?
Blood in the anterior chamber
What is a dislocated lens?
Blunt trauma to the eye can cause damage to the zonule fibers (attach lens to the ciliary body), resulting in dislocation of the lens
Signs and symptoms of a dislocated lens?
Patient has blurry vision or monocular diplopia
What is a retinal detachment?
Retina peels away, e.g: due to trauma (vitreous fluid can leak behind the retina and peel it off)
What is a choroidal tear?
A break in the choroid, Bruch membrane, and the retinal pigment epithelium (RPE) that results following a closed globe injury from blunt trauma
What is a Commotio Retinae?
AKA ‘bruised retina’
Degeneration of the layers of the retina secondary to shock waves caused by blunt trauma/blast injury
Signs and symptoms of Commotio retinae?
Pale and water-logged (oedematous) retina
What is optic nerve avulsion?
May occur due to trauma
Describe lid laceration?
May spare the eyeball itself; can be caused by dog bites
How can fluorescein be used to differentiate between an abrasion and a penetrating injury?
Seidel’s test - assess the presence of anterior chamber leakage in the cornea
Fluorescein can display a leak (Seidel’s +ve, which indicates a penetrating injury)
Other types of penetrating eye injuries (from large objects)?
Corneal laceration
Scleral laceration
Fish-hook injury
What is sympathetic ophthalmia?
Rare cause of bilateral blindness (from a unilateral injury)
Penetrating injury to one eye exposes the intra-ocular antigens; there is an auto-immune reaction in both eyes and inflammation
Areas that small particles (foreign bodies) can cause damage to in the eyes?
- Sub-tarsal
- Conjunctival
- Corneal
- Intra-ocular
- Intra-orbital
When would suspicion arise of a penetrating foreign body?
If the: • Pupil was irregular • Anterior chamber was shallow • Localised cataract • Gross inflammation
Ix for potential intra-ocular foreign bodies (IOFBs)?
Always X-RAY; these can be taken with different eye positions, e.g: looking up and then down, to see if the particle is capable of movement
Causes of chemical burns?
Alkali - easily and rapidly penetrate to cause:
• Cicatrising changes to the conjunctiva and cornea
• Penetrates the intra-ocular structures
Acid - coagulates proteins but has little penetrative potential
Burn can lead to corneal scarring and vascularisation; the end-stage of scarring is potentially devastating
Signs of an alkali burn?
Limbal ischaemia and a totally avascular cornea (china-white cornea), which is abnormal
Important Hx points with a chemical injury to the eye?
Nature of the chemical
When it occurred
Irrigation at the event
LIME/CEMENT (beware)
Mx of a chemical injury to the eye?
Check Toxbase if available (contains information and guidelines about different chemicals)
Check pH (with universal indicator paper; normal tear film is slightly alkaline)
IMMEDIATE IRRIGATION (with a minimum of 2 litres of saline OR until the pH is normal)
Then assess at slit lamp (after irrigation)
