The Abnormal Eye

Question 1

What is Microphthalmia?

Answer 1

abnormally small eye

Question 2

What are the three main causes of Micropthalmia?

Answer 2

Maldevelopment of the globe during foetal development
Globe trauma causing atrophy of the globe
Enophthalmia (sunken eyes)- due to pain, reduce fat, muscle atrophy

Question 3

What is Buphthalmia?

Answer 3

Large eye

Question 4

What are the three main causes of Buphthalmia?

Answer 4

Primary Glaucoma e.g. congenital/ inherited
Secondary Glaucoma due to intraocular tumours
Seemingly larger eyes due to being pushed forward by an abscess/ mass or appear large due to different coloured iris

Question 5

What is the first step in examining whether an eye is truly Micro/Buphthalmic?

Answer 5

Check the line perpendicular to the skull axis to asses the symmetry of the face and orbital socket

Question 6

Give an example of a primary glaucoma

Answer 6

Angle closure glaucoma- the iris bulges. which blocks the drainage angle. As a result, fluid can’t circulate through the eye and pressure increases (aqueous outflow obstruction)

Question 7

What does it mean if a globe is proptosed?

Answer 7

the eyelids have become trapped behind the globe equator

Question 8

When a patient suffers from Ocular Proptosis what do we need to consider when repairing it?

Answer 8

• Rupture of multiple extraocular muscles
• Eye blood supply could be compromised
• Retinal detachment or globe rupture (look for signs of Hyphaema)
• Dolichocephalic breeds have a worse prognosis than Brachycephalic

Question 9

Can cats suffer from Ocular Proptosis? If so is it common?

Answer 9

Yes but because the orbital rum is nearly all limited by bone their globe is usually well protected so requires a lot of force to cause proptosis- this means you also need to consider orbital fractures if a cat does present with this