Trauma

Question 1

What chemical can be used to see the the epithelium of the eye?

Answer 1

Fluorescein

Question 2

What is a blowout fracture?

Answer 2

Fracture of inferior wall of orbit

Question 3

Which wall of the orbit is commonly the thinnest?

Answer 3

Medial wall

Question 4

What structure should you be worried about in a blow out fracture?

Answer 4

Infraorbital neurovascular bundle

Question 5

How should a possible globe rupture be handled?

Answer 5

Carefully! Don’t apply too much pressure

Question 6

What is uveitis?

Answer 6

Inflammation of middle layer which includes iris, ciliary body and choroid

Question 7

What are the signs of traumatic uveitis?

Answer 7

Photophobia

Dilated pupils

Question 8

What is hyphaema?

Answer 8

Blood in the anterior chamber

Question 9

What does a hyphaema look like?

Answer 9

A meniscal level of the inferior iris.

Question 10

How does hyphaema cause raised interglobular pressure?

Answer 10

Increased volume in globe.

Cells clog trabecular meshwork at canal of Schlemm and prevent efficient drainage

Question 11

What does a retinal detachment look like?

Answer 11

Tortuous vessels

Fold-like appearance with fluid under retina

Question 12

What symptoms may the patient have with retinal detachment?

Answer 12

Flashes

Floaters

Question 13

How might a choroidal tear appear on fundoscopy?

Answer 13

White semi circular line adjacent to the optic disc

Question 14

What is commotio retinae?

Answer 14

A bruised retina.

Settles itself in weeks.

Question 15

What is an optic nerve avulsion?

Answer 15

The nerve separates from the globe leaving zero vision.

Caused by blunt trauma

Question 16

What is the difference in penetrating and perforating?

Answer 16

Perforating- injury goes whole way through the structure.

Penetrating- single sided injury

Question 17

What is sympathetic ophthalmia?

Answer 17

When a penetrating injury to one eye causes an auto-immune reaction in both eyes.

Question 18

How is a sub-tarsal foreign body treated?

Answer 18

Invert the eyelid and remove body

Question 19

How is a corneal foreign body treated?

Answer 19

Local anaesthetic and use a needle as a spatula to remove

Question 20

When is a penetrating foreign body suspected?

Answer 20

If irregular pupil, gross inflammation or localised cataract.

Question 21

Why do cataracts form in a foreign body?

Answer 21

If the body touches the lens

Question 22

What investigation should be done for an intra-ocular foreign body?

Answer 22

X ray

Question 23

What is the difference in an alkali burn and an acid burn?

Answer 23

Alkali quickly penetrates intraocular structures.

Acid coagulates proteins on surface but no further

Question 24

Would you rather have an acid burn or an alkali burn?

Answer 24

Acid.

Not as damaging!

Question 25

What system is used to check the chemicals in the substance that caused the burn?

Answer 25

ToxBase

Question 26

Why do alkali burns penetrate the eye more quickly?

Answer 26

Tend to be lipophilic.

Tissue secretes proteolytic enzymes which enhances the damage

Question 27

What does limbal ischaemia denote?

Answer 27

Poor prognostic factor in alkali burns

Question 28

What can limbal ischaemia lead to?

Answer 28

Corneal scarring
Corneal vascularisation
Adhesions

Question 29

How are chemical burns best treated?

Answer 29

Quick history and check of substance
Check pH
Irrigate +++

Question 30

What should the pH of the eye be?

Answer 30

pH 7