Eye Health

Kerryn squints in the sun as if trying to organise her knowledge into a logical flow.

She begins by saying, “Sometimes owners think that tears and brown stains on the hair around the eyes (especially seen in white-haired dogs) are normal ¹. They are often symptoms indicating an underlying problem and starting early treatment will prevent more serious issues in the future.” The truth is that the sooner your pet is seen by a vet or specialist, the greater your chances are to correct disorders that could cause loss of eyesight in the future.

Corneal ulcers, ‘dry eye’, lens dislocations, displaced globes (eyeballs), deformed eyelids, glaucoma, cataracts, ‘cherry eye’ and physical damage—so much can go wrong with your pet’s eyes.

But, as Kerryn explains, it is vital to understand what qualifies any of these as an emergency.

When is an eye issue a serious issue?

Corneal Ulcers

I have heard the cornea described as the “window or windshield of the eye”; what a fantastic description for a truly magnificent little thing! A tear film (much like a waterproof barrier you might apply to your window glass) protects and nourishes the cornea. The cornea in turn has an outer layer of specialised, protective and regenerative skin-like cells, two more layers and a rich network of nerves—but notably, no blood vessels. Behind the cornea, a clear and nutrient-rich fluid keeps everything bathed and protected.

Ulcers on the cornea are commonly caused by physical trauma (from a sharp object, scratching, ingrown lashes, rubbing or chemical contact) but diseases like dry eye or diabetes can also lead to ulcers.

The anatomical shape of brachycephalic (flat-faced) dogs’ skulls predispose the breeds to ulcers too. These breeds suffer from many ocular diseases and are especially prone to corneal erosions. For example, many are unable to close their eyelids completely and the exposed part of the globe dries and ulcerates¹.

An untreated corneal ulcer can lead to corneal scaring and even perforation. In the case of corneal perforation prompt surgical intervention may save the eye or it may need to be removed.

Signs that your pet could have an eye ulcer are: redness, rubbing at the eye, squinting (or holding the eye closed), lots of ocular discharge and, in severely painful cases, loss of appetite and even behavioural changes. As there are no blood vessels in the cornea, you won’t see bleeding from an ulcer in the early stages.

Kerryn advises visiting the vet as soon as an ulcer is suspected. Superficial ulcers or abrasions are treatable and, once the cause has been removed, can heal quite rapidly. So, it makes sense that a timely consultation with a vet could save your pet’s eyesight.

Dry eye

Dry eye ( Keratoconjunctivitis sicca) is caused by a deficiency in the production of tears that lubricate the eye². Tears contain water, fats, proteins, oxygen, nutrition and anti-bacterial agents—all of which keep the eye moist and protected.

There are multiple reasons why glands and tear films may be dysfunctional but most commonly dry eye is caused by a faulty immune response—the immune system destroys tear-producing glands. Other causes include endocrine diseases, infectious agents, nervous system disorders and some types of medication.

Although the condition is not breed-specific, certain types of pets are predisposed to dry eye: Boston Terriers, Yorkshire Terriers, Cavalier King Charles Spaniel and English Bulldogs to name a few³.

The most prominent signs of dry eye is a thick grey to green discharge. The globe can appear crusty, dry and dull. These eyes will be red and uncomfortable and affected pets may also hold their eyes closed. The condition affects the tear film and nerve-rich cornea first, this is painful and irritating to your pet.

Dry eye may be a symptom of other disorders or diseases. Unless those issues are addressed, dry eye cannot be cured. However, treating dry eye with the correct medication —unfortunately life-long—ensures a good quality of life for your pet.