Feline Ophthalmology Series

August 20, 2026

Part Four: Other Conditions to Keep an “Eye” On

Susan Cook Henry 

In the last of this ophthalmology series, we touch on other eye conditions that cats may experience – a couple more common than the others. At the very least, you can add these to your feline ophthalmology vocabulary!

Conjunctivitis

One of the most common conditions cats may experience, conjunctivitis sometimes accompanies other anomalies previously discussed. Simply put, conjunctivitis causes the delicate soft tissues lining the inside of the lower and upper eyelids to become inflamed. Sometimes the tissues are exposed, and there is usually a thick, mucous-like discharge from the eyes. This is something humans can experience as well, most often referred to as “pink eye.” Infectious conjunctivitis is most commonly caused by “agents such as bacteria, viruses, and fungi.”¹ Sometimes, “viruses such as feline viral rhinotracheitis (FVR), also known as feline herpesvirus or feline calicivirus, are the initial cause of inflammation. Primary viral infections are often complicated by secondary infections with a variety of bacteria including Streptococci and Staphylococci.”¹ These variations make it very important for a veterinarian to diagnose the specific cause of the conjunctivitis using certain testing methods before prescribing ophthalmic medications targeted to treat the infection properly.

Blepharitis

When you notice swelling and inflammation of the eyelids accompanied by a crusty discharge along the eyelids, your cat may have a case of blepharitis – which sometimes occurs concurrently with conjunctivitis.

Blepharitis is very common in cats, and most will develop it at some point in their lives. If an infection is causing blepharitis, the infection may be contagious to other cats. Blepharitis is not typically an emergency unless there is trauma to the eye due to an accident. Blepharitis may cause your cat to paw at their eye, risking injury. Placing an e-collar or recovery cone on your cat until they can see a veterinarian may help reduce self-injury to the eye while you wait for your appointment.²

Your veterinarian will likely perform diagnostic tests to determine the source of the swollen eyelids. These may include a retinal exam, fluorescein stain of the cornea, swab testing of inside of the eyelids, nose and/or throat to be cultured at a laboratory to see if an upper respiratory infection is involved, cytology (skin scraping) around the outer eyelids, and bloodwork to rule out potential Feline leukemia virus (FLV) and Feline immunodeficiency virus (FIV).² A combination of oral and topical medications may be prescribed, and the condition should improve noticeably within 7 to 14 days. 

Entropion

You know how it feels when one of your eyelashes (or any foreign object) gets into your eye and rubs the corneal surface, making you try everything you know to get it out. Now imagine part of your lower eyelid rolling in and allowing your lashes to constantly rub the cornea – a condition called entropion. It can happen to humans or any species of mammal but is most common in cats and dogs. If it happens to your cat, they will be in pain and unable to resolve the issue: veterinary care will be required immediately.

Entropion can be congenital (present at birth), occur with developmental/anatomical changes with maturity, or can be secondary or acquired:

• Pain-related: Spastic entropion is the most common type of entropion in cats. This type develops secondary to chronic squinting from painful eye diseases, such as viral or bacterial eye infections,corneal ulcers, or dry eye, that cause involuntary ocular muscle spasms and subsequent inward rolling of the eyelid.The eye’s anatomy is initially normal, but chronic irritation, especially from feline herpesvirus-1, causes damage that is sometimes permanent. Spastic entropion often involves only one eye, but can involve both.
• Injury-related: Cicatricial entropion is uncommon in cats and happens when the eyelid is damaged or scarred because of a previous injury.
• Age-related: Involutional entropion occurs most often in senior cats and involves the age-related loss of the fat pad behind the eye, causing the eye to “sink in” slightly, allowing the eyelids to abnormally roll.³

As with most other eye anomalies, the veterinarian may use a variety of tests to determine the cause of the entropion, including a topical anesthetic, fluorescein stain, intraocular pressure test, or Schirmer tear test. The diagnosis will determine the path to repairing the entropion, and is dependent on the individual cat and the best way to proceed depending on severity. Pain-relieving medications, antibiotic eye drops/ointments, and oral antiviral medications may be prescribed to help heal the underlying issues which may have caused the entropion. In some cases, however, surgical repair may be necessary. If damage to the cornea has occurred, an eyelid may be “tacked” into a position, relieving the entropion while the cornea heals. This alone may allow the eyelid to return to a normal position. But in many cases, a veterinary ophthalmologist will remove “a small elliptical wedge of eyelid skin for correction. By removing the ideal required amount of eyelid skin, tailored to each individual cat, this creates an eyelid that fits well into the eyeball and no longer rolls onto the eye.”³ In addition, “Some veterinary ophthalmologists may use hyaluronic acid (HA) injections as an alternative to surgery, especially in a senior cat who is a poor candidate for anesthesia.”³ Recovery is managed with a recovery cone or collar, with most extremely fine sutures dissolving on their own within 10-14 days post-op. Your ophthalmologist will do a recheck within this time frame.

Progressive Retinal Atrophy (PRA)

“Progressive retinal atrophy (PRA) is a group of degenerative diseases that affect photoreceptor cells. With this disease, the cells deteriorate over time, eventually leading to blindness in the affected cat.”⁴

There are two main forms of this condition that occur in cats:

• Retinal dysplasia, an early onset or inherited form that is typically diagnosed in kittens around two to three months of age, and
• Progressive retinal atrophy (PRA), a late onset form that is detected in adult cats, usually between the ages of two to five years.⁴

“The first sign that is usually noticed in a cat with PRA is night blindness. Affected cats tend to be nervous at night, may be reluctant to go into dark rooms, or may bump into things when the light is dim. Pet owners with cats that are developing PRA often observe that their pet’s eyes have become very reflective when light shines on them, and that the pupils are more dilated than normal. Both eyes are affected.”⁴ Over time (usually two to four years), the cat’s vision will continue to deteriorate, leading to total blindness: there is no cure. Fortunately, cats are not as dependent on their vision as humans and adjust well in familiar surroundings by use of other senses.

PRA is a heritable (genetic) trait, most commonly occurring in Abyssinian, Bengal, and Persian cats. Responsible breeders remove affected cats from their breeding programs to eliminate this trait from their bloodlines and to produce kittens with no genetic trace of the disease. Genetic testing is widely available for PRA, as well as many other feline traits related not only to health but to color and pattern as well.

The Takeaways …

Any time you notice anything “different” about your cat’s eyes, pay attention. Winking, discharge, and/or pawing at the eye may be as little as a stray hair causing irritation – or something more significant. While your current veterinarian may be quite capable of diagnosing an issue, establishing a relationship with a veterinary ophthalmologist early on is well advised if your cat experiences an abnormal eye condition.

References

1. 1. Courtney Barnes, BSc, DVM; Tammy Hunter, DVM; Ernest Ward, DVM, “Conjunctivitis in Cats,”
      (n.d.) VCA Animal Hospitals https://vcahospitals.com/know-your-pet/conjunctivitis-in-cats 
      2. Rhiannon Kohler, DVM; “Blepharitis in Cats,” September 1, 2023. Pet MD; https://www.petmd.com/cat/conditions/eyes/blepharitis-cats
      3. Lauren Jones, VMD; reviewed by Molly Price, DVM. “Entropion in Cats: What It Is and How to Treat,” updated October 29, 2025. https://www.petmd.com/cat/conditions/eyes/c_ct_entropion
      4. Tammy Hunter, DVM; Ryan Llera, BSc, DVM; Cheryl Yuill, DVM, MSc, CVH; “Progressive Retinal Atrophy in Cats,” n.d. https://vcahospitals.com/know-your-pet/progressive-retinal-atrophy-in-the-cat