Trauma Flashcards
What chemical can be used to see the the epithelium of the eye?
Fluorescein
What is a blowout fracture?
Fracture of inferior wall of orbit
Which wall of the orbit is commonly the thinnest?
Medial wall
What structure should you be worried about in a blow out fracture?
Infraorbital neurovascular bundle
How should a possible globe rupture be handled?
Carefully! Don’t apply too much pressure
What is uveitis?
Inflammation of middle layer which includes iris, ciliary body and choroid
What are the signs of traumatic uveitis?
Photophobia
Dilated pupils
What is hyphaema?
Blood in the anterior chamber
What does a hyphaema look like?
A meniscal level of the inferior iris.
How does hyphaema cause raised interglobular pressure?
Increased volume in globe.
Cells clog trabecular meshwork at canal of Schlemm and prevent efficient drainage
What does a retinal detachment look like?
Tortuous vessels
Fold-like appearance with fluid under retina
What symptoms may the patient have with retinal detachment?
Flashes
Floaters
How might a choroidal tear appear on fundoscopy?
White semi circular line adjacent to the optic disc
What is commotio retinae?
A bruised retina.
Settles itself in weeks.
What is an optic nerve avulsion?
The nerve separates from the globe leaving zero vision.
Caused by blunt trauma
What is the difference in penetrating and perforating?
Perforating- injury goes whole way through the structure.
Penetrating- single sided injury
What is sympathetic ophthalmia?
When a penetrating injury to one eye causes an auto-immune reaction in both eyes.
How is a sub-tarsal foreign body treated?
Invert the eyelid and remove body
How is a corneal foreign body treated?
Local anaesthetic and use a needle as a spatula to remove
When is a penetrating foreign body suspected?
If irregular pupil, gross inflammation or localised cataract.
Why do cataracts form in a foreign body?
If the body touches the lens
What investigation should be done for an intra-ocular foreign body?
X ray
What is the difference in an alkali burn and an acid burn?
Alkali quickly penetrates intraocular structures.
Acid coagulates proteins on surface but no further
Would you rather have an acid burn or an alkali burn?
Acid.
Not as damaging!
What system is used to check the chemicals in the substance that caused the burn?
ToxBase
Why do alkali burns penetrate the eye more quickly?
Tend to be lipophilic.
Tissue secretes proteolytic enzymes which enhances the damage
What does limbal ischaemia denote?
Poor prognostic factor in alkali burns
What can limbal ischaemia lead to?
Corneal scarring
Corneal vascularisation
Adhesions
How are chemical burns best treated?
Quick history and check of substance
Check pH
Irrigate +++
What should the pH of the eye be?
pH 7
