Week 2.02 Ocular Emergencies Flashcards
Which cause more serious ocular injuries alkali or acids
Alkalis
E.g. ammonia, sodium hydroxide, calcium hydroxide, magnesium hydroxide
Alkali
Lipophilic and hydrophilic
Easily penetrate ocular tissues: liquefaction necrosis - transformation of tissue into a liquid viscous mass
Acids
Can cause serious ocular injuries
Induce protein coagulation via denaturation
Forms protective protein layer: coagulation necrosis - limits penetration into deeper surfaces
What are symptoms of chemical injuries
- immediate pain
- redness
- reduced vision in affected eye
- significant reflex lacrimation (tearing)
- record the type of chemical
Signs of chemical injuries
- Burns to eyelid and surrounding skin
- conjunctiva inflammation
- conjunctival chemosis
- significant reflex lacrimation (tearing)
Limbal ischaemia - signs
- chemical injuries damage superficial limbal blood vessels
- corneal stem cells located around the limbus
- ischaemia may damage stem cells
- look for peri limbal blood vessels which appear blanched or whitened
Signs the cornea has been damaged
May be mild: superficial punctate keratitis
May be severe: loss of entire epithelium
Corneal oedema (swelling)
Also:
Cells in ant chamber
Raised iop
What is the management for chemical injuries
Irrigate - wash out with saline solution or tap water of saline not available
At least 30 minutes
Remove debris from fornices with cotton bud
Refer the px as emergency to ophthalmologist
Very mild cases such as cl solution accidents can be managed by optom with artificial lubricants
What’s a foreign body
- Grit or dirt blown into eye by strong wind
- Fragments of metal from hammering or grinding
- Small pieces of wood or plastic
What’s the symptoms of a foreign body in the eye
- Sudden onset foreign body sensation in eye
- Conjunctival hyperaemia
- Reflex lacrimation
- VA depends on location of foreign body
Signs of foreign body
- Fluorescein slit lamp examination
- Evert both lower and upper lids
- Check for multiple foreign bodies
o Lids
o Bulbar conj
o Palpebral conj
o Cornea - Determine depth of any corneal foreign body
Management of foreign body
- anaesthetic before attempting to remove
- should only attempt to remove superficial foreign bodies
- very superficial foreign bodies may be dislodged by irrigating with saline solution
- superficial conjunctival foreign bodies may be removed with sterile cotton bud at slit lamp
- soak bud in saline
- deep conjunctival refer
- superficial corneal - hypodermic needle - further training
Deep corneal refer
Corneal abrasion
- Common reason for emergency eye examination
- Corneal damage which has resulted in loss of tissue
- Tissue loss is usually confined to epithelium
Risk factors for corneal abrasions
- Contact lens wear
- Corneal dystrophies
- Dry eye
- Diabetes
Symptoms of corneal abrasions
- Sudden onset, sharp pain
- Conjunctival hyperaemia
- Lacrimation
- Photophobia
- VA?
What are the signs of corneal abrasions
- Slit lamp with fluorescein
- Dye pools in area of abrasion
- Estimate size of abrasion (width and height)
- Examine depth (optic section)
What’s the management for corneal abrasions
- Exclude foreign body (evert lids)
- Do no patch eye
- Oral analgesic (paracetamol, ibuprofen)
- Artificial tears and ocular lubricants
- Prophylactic antibacterial (e.g. chloramphenicol)
- Topical non- steroidal anti-inflammatory drug (e.g. diclofenac sodium)
Blunt trauma
- Sport injuries
- Violence
- Domestic accident (e.g. fall)
Symptoms of blunt trauma
- Pain
- Reflex lacrimation
- Swelling and bruising around eye
- VA may be reduced
Signs of blunt trauma
- Lid bruising
- Subconjuctival haemorrhage
- Common finding
- Usually not serious
- Typically resolves spontaneously within 5-10 days
Iridodyalysis
Iris separates from ciliary body at the root of iris
Traumatic cataract
Retinal tear/detachment
Choroidal ruptures
Always dilate px with recent history of blunt ocular trauma
Enthopthalmos (sunken eyes)
Eye is displaced into socket
Orbital blowout
Hyphaema
Blood between cornea and iris
Causes secondary glaucoma
