Eye injuries Flashcards
Define corneal abrasion.
scratch/ damage to cornea
How do corneal abrasions occur?
- Contact lens – may be associated infection w/ pseudomonas.
- Foreign body
- Fingernail/ eyelashes
- Entropion
- Chemicals, e.g acid – severe eye damage and vision loss.
How does corneal abrasion present?
- Painful, red eye – due to dilation of blood vessels on surface.
- Foreign body sensation
- Watery eye
- Blurry vision
- photophobia
How is corneal abrasion diagnosed?
- fluorescein stain (yellow-orange color) – collects where there is abrasion/ ulcer.
- slit lamp examination – only seen if abrasion is signif
- fundoscopy – loss/decreased red light reflex suggest major abrasion
Management of corneal abrasion.
red eye and threat to vision - same day opthal referral.
analgesia.
eye patch that seals lid.
cyclopentolate/ diclofenac drops to dilate pupil (reduces iris spasm).
Abx eye drops if needed
FOLLOW UP AFTER 24 HRS.
How are chemical eye burns treated?
check toxbase.
immediate eye irrigation w/ saline until pH returns to normal.
paracetamol (analgetic eye drops only to be used after irrigation).
cyclopentolate - dilate pupil and stop painful eye spasms.
topical Abx and corticosteroid if needed.
Define hyphema.
the collection of blood in the anterior chamber of the eye.
ant chamber = between cornea and iris.
the blood may cover part or all of the iris and the pupil. can partially or fully block vision.
mostly due to trauma, spontaneous hyphemas can occur in the setting of sickle cell disease or other increased bleeding states.
How do foreign bodies in the eye present?
- Red, watery eye.
- Painful
- Blurry vision (signif vision loss if body is intraocular).
- Hyphema
How is foreign body diagnosed?
- clinical
intraocular body – CT orbit
How are foreign bodies in eye managed?
- remove - numb w/anaesthetic eye drops, and fluorescein drops to use slit lamp to guide removal.
- iron and steel leave ring of rust - remove w/ sterile needle.
- sweep cotton wool inside of eye to collect tiny particles.
- intraoccular - Abx (IV or drops) and tetanus vaccine.
Causes of a conjunctival foreign body?
- dust or grit blown into eye via wind.
- fb gravitates into lower fornix - remove w/ cotton bud.
sub tarsal FB - presentation, diagnosis and Mx?
FB stuck in eyelid - pain on blinking.
Dx - Fluorescein staining may show vertical corneal abrasions ( ‘ice rink’).
Tx - ever eyelid and remove fB w/ cotton wool. Abx (chloramphenicol, fusidic eye drops).
Mx of corneal FB?
- remove w/ cotton wool first.
if fail - 23g needle. - Abx - patient to return is symp persist past 36hrs.
- Refer patients with large, deep or incompletely removed FB, or if a rust ring present.
Define blowout fracture?
- Break in 1 or more of the 7 bones that surround the eye.
Pathophysiology of blowout fracture?
- object strikes the eye - forces transmitted to orbit - bones break from pressure by force of trauma.
- herniation of contents into maxillary and ethmoid sinus.
RF of blow out fracture?
- children
- more common in boys.
How does a blowout fracture present?
- simple fracture - minimal/ no diplopia, minimal or no enophthalmos when healed.
- ecchymosis, tenderness and swelling around eye.
- bleeding from orbital haemorrhage or eyelid.
- epistaxis
- vertical diplopia
- Infraorbital anesthesia (cheek, nose, upper teeth and gums, upper lip etc) – IPSILATERAL – due to damaged nerves.
- sub cut emphysema.
- Reduced eye movement due to trapped inf rectus muscle – which restricts upward gaze.
- enopthalmos and exopthalamus.
Define vertical diplopia.
double vision esp looking up
Define lid ecchymosis.
blood leaks from a broken capillary into surrounding tissue under the skin. This causes discoloration.
in eyelid
how are blow out fracture diagnosed?
CT orbit
Mx of blow out fracture?
simple - no surgery.
- ice, decongestant to drain blood and fluid accumulating in sinuses.
- avoid blowing nose for 10 days.
- oral steroids and Abx (co-amoxiclav).
- surgery
Define white blow out fracture.
when there is minimal bruising but signif entrapment of muscles (have N +/- V esp on upward gaze).
Mx - surgery in 48-72 hrs due to risk of necrosis.
Define retrobulbar haemorrhage.
AKA orbit compression/ compartment syn.
Accumulation of blood in the retrobulbar space (behind eyeball).
RF for retrobulbar haemorrhage.
- Orbital trauma
- Anticoagulation
- AVM
- Valsalva maneuver, HTN in Post-eye surgery
- retrobulbar anesthesia
How does retrobulbar haemorrhage present?
severe pain, difficuly opening eyelids.
proptosis
vision loss
periorbital ecchymosis
eyelid hematoma and subconjunctival haemorrhage if due to trauma.
N +/ - V
Ophthalmoplegia
Define Ophthalmoplegia
paralysis of extra-ocular muscles that control eye movement
Dx of retrobulbar haemorrhage.
clinical
CT orbit
Management of retrobulbar hameorrhage.
dont wait for CT.
- canthotomy to be done within 2 hrs of onset of blindness or proptosis.
- IV acetazolamide and IM/IV hydrocortisone (less effective) to reduce pressure.
What is canthotomy?
cutting canthus (corner of eye) to release pressure
RF for globe rupture?
- ocular surgery
- trauma
How does globe rupture present?
- pain
- loss of vision
- diplopia
- distorted shape of glove
- herniation through sclera visible
How is globe rupture diagnosed?
CT oribit
- The Seidel test
What is the seidel test>
used for globe rupture Dx.
measure aq humour leakage from ant chamber. The clear band is caused by dilution of the fluorescein by leaking aqueous fluid.
Mx of globe rupture?
- eye patch is contraindicated - use fox shield or bottom of polystyrene cup.
- antiemetic - prevent valsalva.
- Abx
- tetanus prophylaxis
- NBM
- refer
