There’s almost nothing more instantly recognizable than a cat’s eye. Unique eye colors and shapes make them stand out – and the unique way cat eyes work is actually even cooler.
To learn more about what makes cat eyes so special and how best pet owners can care for their cats’ eyes, we spoke to Dr. Julie Sanders, Director of Operations at Heart+ Paw. And the science behind their eyeballs proves that cats are magical creatures.
What makes cat eyes unique from other animals?
Although the eyes of cats are quite similar to those of humans and other mammals, they have a special reflective structure at the back of the eye near the retina called the “tapetum lucidum”.
“It acts like a mirror, reflecting light onto the retina,” Dr. Sanders told The Dodo. “It’s part of what allows cats to see better than people in low light conditions. It also gives cats’ eyes that cool reflective glow.
Cats also have a third eyelid that hides in the inner corner of the eye and partially covers the eye.
“The partial coverage provided by the third eyelid protects the eye from trauma while allowing some vision,” Dr. Sanders said. “Most people don’t notice the third eyelid unless their pet is sick, injured, or has a genetic abnormality (like a prolapsed tear gland in that eyelid).”
Does the tapetum lucidum allow cats to see in the dark?
“No animal can really see (with its eyes) in total darkness (an absence of light),” Dr. Sanders said. “Cats have anatomical differences that allow them to see in very low light conditions that can appear ‘dark’ to humans.”
The tapetum lucidum helps light-sensitive rods in the retina to be stimulated twice by a single light particle, Dr. Sanders explained. And the rods of cats are also proportioned and focused differently compared to the rods of human eyes.
“Rods, which provide black-and-white vision, are much more sensitive to light and require fewer photons to stimulate vision,” Dr. Sanders continued. “Cats have more rods than humans, which allows for better low-light vision.”
Can cats see colors?
Yes, cats can see some colors, but not all.
“They have cones, or sensors in the retina, that process color,” Dr. Sanders said. “Cats (like dogs) are red-green color blind,” but can see blues and yellows.
What medical conditions or diagnoses can affect the eyes of cats?
Cats’ eyes can be affected by many different medical conditions. Here are some of the most common medical problems in cats that can affect the eyes.
Feline herpes is the most common disease that affects cats’ eyes, Dr. Sanders said.
“[Feline herpes] can cause discharge and ulcers,” she explained. “Almost all cats are infected with the feline herpes virus during their lifetime, and symptoms can range from mild to severe. Eye symptoms include protrusion (raising) of the third eyelid, discharge, strabismus and ulcers.
Rough play, injury from foreign objects, and self-trauma from rubbing or scratching can cause cat eye injuries and problems like corneal ulcers, with symptoms like sensitivity to light , strabismus, watery discharge, dull appearance on the surface of the cornea, and proptosis of the eye (i.e. the eye protrudes from its socket).
“[Proptosis of the eye] is an emergency,” Dr. Sanders said. “If the optic nerve is still intact, it is possible to save the proptosis eye surgically. If not, your cat will need an enucleation to remove the eyeball to regain comfort.
Fortunately, having only one eye won’t affect your cat too much. Depth perception is really the only problem your cat may have after losing an eye.
Rotting teeth can cause abscesses to form in the jawbone, which can cause swelling around the eye, and if not properly treated, “the pressure from this swelling could eventually cause blindness”, said Dr. Sanders.
Cancer in or near the face can also cause swelling, so take your cat to the vet as soon as possible to make sure the swelling is taken care of.
High blood pressure
“Cats can also have retinal detachments due to high blood pressure,” Dr. Sanders said. “Several chronic medical conditions such as kidney disease/failure and hyperthyroidism (both [of] which are common in older cats) can cause high blood pressure.
If your cat has been diagnosed with any of these medical conditions, you should have their blood pressure checked at least every six months. “Yes, there are high blood pressure medications for cats!” added Dr. Sanders.
“Cats can sometimes develop cataracts, which is a modification of the lens that makes it impenetrable to light,” Dr. Sanders said.
Cats, like humans, can actually undergo cataract removal surgery to regain their vision. If your cat has been diagnosed with cataracts, discuss with your veterinarian the pros and cons of cataract surgery for your cat.
Lenticular sclerosis is a natural increase in lens density that occurs with age and is often confused with cataracts because the lens may appear cloudy.
“The two conditions can be difficult to differentiate. If you notice that your pet’s central eye looks blurry, get it checked out!” says Dr. Sanders. “Cataracts often occur with diabetes mellitus, which is treatable but best if diagnosed and treated early.”
Allergies or dust mites
If your cat suffers from allergies or dust mites, she may be losing hair around her eyes. Set her up with a vet-approved pest prevention plan and talk to your vet about what you can do to treat her allergies.
How can pet owners take care of their cats’ eyes?
The easiest way to ensure your cat’s eyes stay healthy is to just be careful.
“Healthy eyes don’t need special care,” Dr. Sanders told us. “The best thing a pet parent can do is pay attention to any changes in their pet’s eyes and [seek] medical care if [they notice] any changes such as strabismus; constant protrusion of the third eyelid; watery, mucous, or colored discharge; cloudy appearance; eye swelling; or swelling around the eye. If your cat exhibits any of these symptoms, it is important to consult your veterinarian as soon as possible.
And keep up to date with annual or semi-annual veterinary appointments. An eye checkup and blood tests are always routine during these exams, and your vet will be able to quickly spot symptoms of diseases that may be affecting your cat’s eye health.
“For first aid purposes, if you need to flush your cat’s eyes for any reason, use an over-the-counter eye wash or saline solution specifically labeled for the eyes,” Dr. Sanders said, and these washes and solutions can be found. in most pharmacies. “Never put anything but saline solution labeled ‘for eyes’ in a cat’s eye,” she continued.
Cats’ eyes are just as amazing and unique as they are, and keeping a close eye (no pun intended!) on your cat’s eye health will help ensure that their vision stays crystal clear for years to come.