Sore eyes are a common feline problem. However, it can sometimes be very hard to decide just how serious the issue is, and whether it can be managed with medication (e.g. eyedrops), or whether surgery is needed.

We’re going to look at some of the most common conditions and treatment options available. From minor irritations to serious issues, let’s start with the basics.

What’s wrong with my cat’s eye?

How do you know when your cat has an eye problem? Well, they’re often uncomfortable, so they give us a lot of clues. Maybe they have a weepy eye, or they are grooming their face more often. One or maybe both eyes might look reddened. The third eyelid may be raised across the globe (that’s what we call the eyeball), or it may be that the eye has changed colour and become reddened or cloudy. In some cases, the eyeball might look bigger than normal. If you see any of these signs, best get your vet to take a look. 

How can my cat’s eye problem be diagnosed?

So, at the vets, you’ll see a few common tests. We start with a good exam of all the external structures from far away, then up-close with an ophthalmoscope. Some pets can find this a bit overwhelming because we have to get really close to their face with our face and the scope. So we take this nice and slow, or we use what looks like a magnifying glass. With this, we are examining the structures inside the eye and figuring out exactly where the problem lies within the in.  

Other tests that we use include gently probing with a moistened cotton bud to check for irritating material like dirt in the conjunctiva around the globe. This can be done as well as the fluorescein dye test, Schirmer Tear Test (STT), tonometry and cytology. 

Let’s look at these individually.

The fluorescein test

This is where we apply one of those orange-tip strips to the eye. This makes the tears take up a yellow-green stain so they look like the green-eyed monster. It might come dribbling down their nose but this is totally normal! We use this to check for breaks in the cornea, which we call ulcers. 

The STT 

Here, we measures the amount of tears the cat produces. This is compared to a normal value to see if there’s a lack of tear production, which can cause drying and lead to infection and ulcers. 

Next, tonometry. 

This is really cool! It’s where we measure the pressure within the eye. It helps us to distinguish between those eyes that are getting bigger and have elevated ocular pressure (this is glaucoma which is a term you’re probably familiar with), from those that look like they’re getting bigger because they’re being pushed out of place by something. 

Cytology can also be done

Looking at cells from the surface of the eye can help us diagnose bacterial, viral and fungal infections. This may also highlight mass-type structures and determine what’s the best treatment. We often use a cotton bud or a special small brush to get a sample to look at under the microscope or send to the laboratory. 

So those are the main ones, often specialists will have even more sophisticated tests they use to help diagnose the problem too. 

Anyway, now we know the signs of eye problems and the ways to diagnose them, what’s next?

When do we need to perform surgery on eyes?

Well, we can’t go into every eye problem because there are a LOT of different things that can go on in there. So, we’ll highlight the ones that are more likely to lead to surgery and why. In some cases, it’s obvious surgery is needed from the outset, in others we have to resort to surgery when medical therapy hasn’t been successful or it’s not appropriate for the pet. 

First up, ulcers 

Eye ulcers can be real nasty things, they’re unpleasant for the cat and take time to heal. Ulcers can be caused by scratches, drying of the cornea (the very front wall of the globe), burns or irritation but also form a part of immune-mediated conditions. They are also common in upper respiratory disease complex where viruses or bacteria can cause conjunctivitis and ulceration of the cornea (often alongside other respiratory or general signs of ill health). 

We see this complex commonly in cats and kittens which live in colonies or mix with lots of other cats. In many cases appropriate antibacterial and antiviral therapy combined with a clean environment and good husbandry like preventing stress and overcrowding in cat households, are enough to control the signs. 

Uncomplicated ulcers will often get better with protection using a buster collar, topical antibiotic drops and painkillers. However, in some cases we have to perform a surgery to place a patch of conjunctiva over the ulcer while it heals, or a small intervention may be done to semi-close the eye temporarily to protect the damaged cornea. In very severe cases of ulceration, however, we might have to remove the eye completely (known as enucleation)

Glaucoma and protruding eyes

Glaucoma can normally be managed with medication. When this doesn’t work, the eye is very painful, poorly visual and affects the pet’s quality of life. Here we may consider surgery to try and re-establish proper drainage from the eye, or even enucleation. 

Enucleation is often also recommended where there is a problem in the tissues behind the eye, like a molar tooth root abscess or a tumour, because without removing it we can’t access the damaged tissue. It’s a shame but only recommended if really necessary. 

Sometimes we also see cases where the eye has ‘popped-out’ of its socket, known as exophthalmos. Firstly, we try to put it back in, but if the muscles of the eye or the globe itself have been severely traumatised, enucleation is the next step.

As you can see, we often choose enucleation as the last resort, where we have painful eyes that just don’t respond to treatment or are too uncomfortable for the patient to tolerate meanwhile. 


Finally, we can’t write about surgery for eyes and not say something about cataracts. A cataract is where the lens of the eye gets so cloudy the light can’t get through to the retina, as it progresses eventually it can lead to blindness. Some are associated with underlying causes like diabetes so the cats have to be well investigated to rule these out before we can do anything about the cataract. The removal of cataracts involves replacing the damaged lens with an artificial one, and can help restore some vision. It is offered by specialists and can help improve the quality of life for some pets. How cool is that!

The bottom line…

Your vet will almost always try to save your cat’s eye and sight. Usually that can be done with medication; however, sometimes, surgical repair is needed. In extreme cases, though, where the eye is painful and badly damaged, it may be better for your cat for the vet to remove the injured eyeball.

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