Ophthalmic emergencies

Question 1

List 6 ocular emergencies

Answer 1

traumatic globe prolapse
Retrobulbar abscess
Acute glaucoma
Anterior lens luxation
Corneal emergencies
Sudden onset blindness

Question 2

describe a globe prolapse

Answer 2

globe is acutely displaced forwards, beyond the plane of the eyelids

Question 3

describe exophthalmos

Answer 3

a degree of forwards displacement of the globe with the eyelids remaining in a normal anatomical position

Question 4

Describe how globe prolase occurs

Answer 4

immediate oedema of the conjunctiva and orbital soft tissue leads to exopthalmos
eyelid spasm further exacerbates the issue and blocks the venous drainage
leading to more swelling and eventual prolapse

Question 5

Are cats likely to have globe prolapses

Answer 5

no- they have deeper orbits and therefore deeper protection

Question 6

List the positive indicators to attempt replacement in grobe prolapse cases

Answer 6

brachycephalic breeds
positive PLR
eye attempting to move

Question 7

List the 2 treatment options for globe prolapse

Answer 7

replacement or enucleation

Question 8

what do we use to clean the eye for surgery

Answer 8

povidine- iodine solution

Question 9

after replacing the prolapsed globe, what can you do to ensure the eye doesn’t reprolapse

Answer 9

temporary tarsorraphy - suture the eyelids together

Question 10

after replacing a globe prolapse, what needs to be done in terms of aftercare

Answer 10

systemic antibiotics (chloramphenicol) and NSAIDs
buster collars
re-evaluate after 10-15 days

Question 11

after globe prolapse occurs, do the animals normally retain vision in that eye

Answer 11

No

Question 12

List the clinical signs of a retrobulbar abscess

Answer 12

acute onset
unilateral
exopthalmos
painful
third eyelid protrusion
ocular discharge
pyrexia
lethargy

Question 13

why are retrobulbar abscesses an ocular emergency

Answer 13

pressure on the optic nerve can cause temporary blindness that if not treated can turn into permanent blindness

Question 14

how can we medically manage retrobulbar abscesses

Answer 14

systemic NSAIDs + antibiotics (amoxiclav +/- metronidazole)
IVFT
topical lubricants

Question 15

List the clinical signs of acute glaucoma

Answer 15

ocular pain
head shy
yelping
dull
vision loss
change in appearance

Question 16

what is the triad of ocular pain signs

Answer 16

blepharospasm
increased lacrimation
photophobia

Question 17

what can we see in the eye in acute glaucoma cases

Answer 17

corneal oedema
episcleral congestion
and/or fixed/dilated pupils

Question 18

how do we diagnose acute glaucoma

Answer 18

tonometry

Question 19

normal IOP in dogs and cats

Answer 19

10-25 mmHg

Question 20

List some medications to reduce IOP

Answer 20

prostaglandin analogues (latanoprost)
carbonic anhydrase inhibators (nrinzolamide, dorzolamide)
beta-blockers

Question 21

when can we give IV mannitol for glaucoma

Answer 21

if they are not responding to any drops

Question 22

Describe acute glaucoma medical treatment

Answer 22

reduce IOP with prostaglandin analogues, carbonic anhydrase inhibitors or beta-blockers

analgesia

referral ASAP

Question 23

if we lose one eye to acute glaucoma what do we need to make sure to do

Answer 23

investigate the second eye for an underlying cause

Question 24

what breeds are predisposed to anterior lens luxation

Answer 24

terriers

Question 25

what happens when the lens luxates anteriorly

Answer 25

it can block the drainage of the eye

Question 26

List the clinical signs of anterior lens luxation

Answer 26

acutely painful
glaucoma
corneal oedema

Question 27

what can sometimes differentiate anterior lens luxation from primary glaucoma

Answer 27

the presence of the lens outline in the anterior chamber

Question 28

Describe how to treat anterior lens luxation

Answer 28

referral for surgery- remove or push lens backwards
analgesia
IOP reducing medication - need to use carbonic anhdyrase inhibitors or betablockers as prostaglandin analogues won’t be helpful

Question 29

why do prostaglandin analogues not help in anterior lens luxation cases

Answer 29

because the lens is blocking the draining, you therefore can’t increase the draining

Question 30

what is an aphakic crescent in the pupill

Answer 30

a small crescent that indicates that the lens has subluxated

Question 31

List 4 corneal emergencies

Answer 31

chemical injury
FB
Melting ulcer
severe lacerations

Question 32

Describe how to treat chemical injuries to the eye

Answer 32

immediate irrigation of the ocular surface using flush/water
test pH of conjunctiva
early specialist advice

Question 33

if there are large corneal foreign bodies, what should we do

Answer 33

provide analgesia and a buster collar and refer immediately

Question 34

List the clinical signs of a melting corneal ulcer

Answer 34

acute
painful
gloopy discharge
corneal oedema
anterior uveitis

Question 35

List 8 causes of sudden onset blindness

Answer 35

Acute glaucoma
Acute uveitis
Intraocular haemorrhage
Retinal detachment
Optic neuritis
SARD (Sudden Acquired Retinal Degeneration)
Toxicity
Intracranial lesion