Occular Trauma

Question 1

how can an area of epithelial loss be identified?

Answer 1

by use of fluorescein drops

Question 2

what are the important aspects of assessment of ocular trauma?

Answer 2

history of incident
visual acuity
examine eye (conjunctiva, lids, cornea, anterior segment, pupils, fundus)
use fluorescein drops to identify area of epithelial loss

Question 3

how may the eye react to blunt trauma?

Answer 3

the globe of the eye can protrude in any direction and damage a wall of the orbit
= orbital blow out fracture

Question 4

sign on blow out fracture on CT?

Answer 4

tear drop sign

eye herniates through the hole in the orbital wall

Question 5

what is a white eye blow out fracture?

Answer 5

blow out fracture with very few clinical signs apart from reduced mobility of the eye
- direction of mobility problem depends on area of fracture and muscle damaged

Question 6

what causes iritis/uveitis?

Answer 6

due to breakdown of blood-aqueous barrier

Question 7

what is hyphaema?

Answer 7

blood in the anterior chamber

Question 8

where can tearing occur in the eye?

Answer 8

can tear where the iris joins
lens can dislocate
retinal detachment
choroidal tear

Question 9

sign of dislocated lens?

Answer 9

disruption of zonules

zonule fibres can be seen in eye

Question 10

can retinal detachment occur from trauma?

Answer 10

yes

Question 11

what is commotion retinae?

Answer 11

bruising of retina

Question 12

what does commotion retinae look like?

Answer 12

abnormal colouring of retina

darker with whiteish sheen over retina

Question 13

how is commotion retinae managed?

Answer 13

usually resolves on its own

Question 14

what is optic nerve avulsion?

Answer 14

..

Question 15

how might a corneal laceration present?

Answer 15

misshapen/irregular pupil or iris
as iris moves to plug the whole in the cornea
aqueous humour can pour out of the hole in the cornea (seidel test)

Question 16

what is sympathetic opthalmia?

Answer 16

penetrating injury to one eye > exposure of intra-ocular antigens > autoimmune reaction in both eyes
inflammation in both eyes
may lead to bilateral blindness from a unilateral injury

Question 17

common sites where foreign bodies can enter the eye?

Answer 17

sub-tarsal
conjunctival
corneal
intra-ocular
intra-orbital

Question 18

how are foreign bodies in the eye managed?

Answer 18

removal of foreign body

antibiotic (chloramphenicol) should be applied 4X daily for a while afterwards

Question 19

what might raise suspicion of penetrating foreign body?

Answer 19

irregular pupil
shallow anterior chamber
localised cataract (can come on in a matter of hours after injury)
gross inflammation

Question 20

how is an intra-ocular foreign body investigated?

Answer 20

X ray of orbits

good history

Question 21

what can cause a chemical burn in the eye?

Answer 21

alkali

acid

Question 22

how does acid affect the eye?

Answer 22

coagulates proteins

Question 23

how does alkali affect the eye?

Answer 23

easy rapid penetration
cicatrising changes to conjunctiva and cornea
penetrates the intra-ocular structures

Question 24

sign of alkali burn?

Answer 24

new evidence of ischaemia

e.g limbal ischaemia

Question 25

possible complications of burns in the eye?

Answer 25

corneal scarring
- usually harmless if in the lumbus/sclera
- can cause visual problems if in the cornea or midline etc
corneal vascularisation

Question 26

how is chemical injury to the eye managed?

Answer 26

thorough irrigation (minimum of 2L of saline or until pH is normal) immediately
quick history
check toxbase
check pH
then assess at slit lamp

Question 27

common cause of chemical injury to eye?

Answer 27

cement (lime in cement)