Q I have suffered from nearsightedness for my entire life. Lately, I’ve been wondering if our cats can have vision problems too (outside of eye disease or something related to the aging process, like cataracts). If so, is there a way to determine this?
Michael R. Cunningham
A Dear Michael: Nearsightedness is a type of vision problem known as a refractive error. The structures of the eye are meant to act as a giant lens, bending incoming light rays to focus images clearly on the retina. When a refractive error is present, the eye is not bending light properly. In the case of nearsightedness (also known as myopia), light rays are focused in front of the retina. In the case of farsightedness (also known as hyperopia), light rays are focused behind the retina. In either case, the result is blurry vision.
Refractive errors can result from abnormalities in the composition or shape of various parts of the eye, or because the eyeball is abnormal in overall length. In people, most refractive errors are easily corrected with glasses or contact lenses, which alter the path of light entering the eye and allow for light to be focused properly on the retina.
Refractive errors are assessed via a technique called streak retinoscopy, in which a beam of light is swept across the eye and its movement observed. Through this technique, ophthalmologists can determine which type of refractive error is present and can calculate the proper prescription for glasses or contact lenses.
Animals can also have refractive errors. Several studies have been done to assess dogs, cats and horses for refractive error. These studies found that most animals have very little refractive error, although certain dog breeds were found to be near- or far-sighted. Adult cats seem to have minimal refractive error. While other eye problems like cataracts or retinal diseases can impair feline vision, your cat probably doesn’t need glasses!
Stephanie Pumphrey, DVM, DACVO
Cummings School of
at Tufts University
Hi!I have a domesticated cat 9yrs male.I suspect refractor error in his eyes.Why?He prefers to see by Rt eye while his Left eye seems to be alright clinically.I can send pictures and videos if needed.Would you like to know more?
My cat Peter went missing about 6 years ago and we found him in the darkest place I’m sure he could find. Once inside I realized his eyes were completely dilated and have been every since. We’ve always assumed he got around chemicals of some type. The Vets have no idea and he can see. He’s been able to hunt etc. His eyes are completely black, pupil, and obviously the bright sun hurts his eyes. I’d love to get sunglasses for him but don’t know if they make ones that would really help & stay on. The once I’ve seen online all mostly are novelty items. And they’re cheap so I can’t see how helpful they really are. I also don’t know if theres really anyway to realistically keep them on his face.
Any feedback would be so appreciated. He’s 18 now and it’d be nice if he didn’t have to stick to the shadows anymore.
Kati & Peter
My brother graduated from Tuffs undergrad in 1982
My cat of 7 years was born with only 3 paws and a wonky left eye. She as always been very Farrel and has only let me pet her.. and with that it took me a year and a half with her being as a kitten.
She seems afraid of any sudden movements.
I suspect her eyes are mis-matched in vision and it may mess with her awareness.
Is this correctable surgically, is this even a possibility, or is she just a complete wild ass that doesnt like humans (except for me)?
Do they make a prosthetic paw for cats?